Nasal and oral patient interface

ABSTRACT

A patient interface for communicating fluids to and/or from a patient&#39;s nasal cavity and/or oral cavity is disclosed. In addition, a patient interface for fluid and physiological function monitoring proximate to the patient&#39;s nasal cavity and/or oral cavity is disclosed. An apnea monitor and a method for monitoring apnea are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119(e) fromprovisional U.S. patent application Nos. 60/835,735, filed Aug. 4, 2006,and 60/947,523, filed Jul. 2, 2007, the contents of both of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to improved patient interfaces for carbondioxide sampling, supplemental oxygen delivery, and combined carbondioxide sampling and supplemental oxygen delivery. In addition, thepresent invention relates to nasal and oral patient interfaces for gasand physiological function monitoring, and for other monitoringmodalities. The present invention is further related to the combinationof a nasal carbon dioxide sampler and a nasal/alar centralphotoplethysmographic sensor that can be used as an apnea detector.

2. Description of the Related Art

A sidestream type of gas sampling system transports a flow of gas fromthe patient's airway through a sampling tube, to a sample cell, wherethe constituents of the gas are measured by a gas sensing system. Gasesare continuously aspirated through the sampling tube, and into thesample cell, which is located typically within a gas measurementinstrument. Gases are commonly sampled at flow rates ranging from about50 ml/min to about 250 ml/min.

For purposes of description, the discussion herein is focused on patientinterfaces and/or cannulas for use with human patients, it beingunderstood that the present invention is not limited in scope only touse with human patients and can beneficially be used in various othercontexts. For example, the present invention may also be used in thearea of veterinary medicine where the “patients” are animals.

Different types of oral/nasal cannulas are used to deliver oxygen topatients who need assistance to breathe properly, to collect a gassample from patients to monitor respiration, or to perform bothfunctions. Such cannulas are used when direct ventilation is notprovided. The term “oral/nasal” refers to the adaptable configuration ofsuch cannulas, which can be in close proximity to the oral cavity(mouth) or inserted into the nasal cavity (nostril(s) or nares) of thepatient. In either arrangement, a sidestream of the patient's exhaledbreath flows through the cannula to a gas analyzer to be analyzed. Theresults of this non-invasive analysis provide an indication of thepatient's condition, such as the state of the patient's pulmonaryperfusion, respiratory system, and/or metabolism.

Some nasal interfaces for carbon dioxide sampling are perceived failingto remain in position during monitoring and uncomfortable. Also,differences between patients, in particular, in the spacing between thepatient's nostrils, and the spacing between the patient's nose andmouth, as well as differences in airflow from the nostrils should beconsidered.

In addition, the nasal resistance between subjects can varysignificantly. As such, the nasal airflow can often be quite asymmetricbetween the two nostrils. This can affect the efficiency of oxygendelivery, as the delivery will depend upon the nature of an obstructionin one or both nostrils, and how the oxygen is delivered. Existing nasalcarbon dioxide sampling and oxygen delivery cannulas either deliver to asingle nostril, deliver equally to both nostrils, or produce a “cloud”of oxygen, which is inhaled by the subject. A simple means topreferentially direct oxygen to the less obstructed nostril is desired.

In addition to sidestream sampling techniques, the present inventionalso relates to various monitoring techniques. It is known that ifoxygen levels in the blood become very low at peripheral sites, avariety of clinical problems may occur. In addition, diseases, acuteinjuries, and other conditions can adversely affect blood flow to and inthe limbs, and poor blood flow reduces the amount of oxygen that iscarried in the blood stream to cells.

In general, blood oxygen levels are currently measured by pulseoximetry, which can be categorized into transmittance and reflectancetypes. Transmittance, or transillumination oximetry, involves theprocess in which a sensor measures light extinction as light passesthrough a portion of blood-perfused tissue. Light is transmitted fromone side of a portion of blood-perfused tissue, and is recorded by adetector situated on the opposite side of the same portion of tissue.Reflectance oximetry, on the other hand, has both the light source andthe detector on one side of the tissue, and measures reflectance backfrom the tissue.

For both types of oximetry, multiple signals from the light sensor, ordetector, may be used to estimate the oxygen saturation in the bloodand/or pulse rate from changes in absorption of the light detectedthroughout blood pulse cycles. The technology is based on thedifferential absorbance of different wavelengths of light by differentspecies of hemoglobin, as known in the art.

Conventional pulse oximetry measurement in certain classes of patients,for instance severely burned patients, can be a significant challenge,yet this monitoring data is vital in operating room and intensive caresettings. Most current pulse oximetric approaches depend upon availableperipheral sites permitting transillumination oximetry, which issufficient for most surgical conditions and procedures. However, in someinstances, such as patients with severe burns, only a few sites may besuitable for the effective placement of the transmitting pulse oximetersensor. These patients often have severely comprised circulatoryfunction, thereby rendering the current peripheral pulse oximeters lesseffective. Therefore, it is desirable to measure to measure oxygensaturation from a central measure.

With respect monitoring, a robust and inexpensive apnea monitor, forexample, particularly for adults, has yet to appear on the market. Inthe United States, an apnea monitor is defined by the Code of FederalRegulations as “a complete system intended to alarm primarily upon thecessation of breathing timed from the last detected breath. The apneamonitor also includes indirect methods of apnea detection, such asmonitoring of heart rate and other physiological parameters linked tothe presence or absence of adequate respiration.” 21 C.F.R. § 868.2377.An easy to apply device with robust and redundant detection methods ofapneas is desired.

The present invention is further concerned with providing a simple wayof performing ambulatory sleep diagnostic studies. An easy to applysingle-site device that provides the ability to sense directly orsurrogates of effort, SpO₂, or flow is desired.

SUMMARY OF THE INVENTION

Accordingly, one aspect of the present invention provides a patientinterface with improved stability and comfort to the patient. Thisobject is achieved by providing a patient interface that includes a bodyportion configured to communicate with at least one fluid path. At leastone nostril interface extends from the body portion and is configured tobe inserted into a nostril of a patient and to be in communication withthe at least one fluid path. A pair flexible stabilizers extend from thebody portion on opposite sides of the body portion and are configured tosubstantially conform to the patient when the interface is mounted tothe patient.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate withfirst and second fluid paths. First and second nostril interfacesproject from a first side of the body portion. The first nostrilinterface communicates with the first fluid path, the second nostrilinterface communicating with the second fluid path, the first and secondnostril interfaces being configured to be inserted into left and rightnostrils of a patient, respectively, when the body portion is in a firstorientation, so as to communicate the first fluid path with the leftnostril and the second fluid path to the right nostril. Third and fourthnostril interfaces projecting from a second side of the body portion,the third nostril interface communicate with the first fluid path. Thefourth nostril interface communicates with the second fluid path. Thethird and fourth nostril interfaces are configured to be inserted intothe right and left nostrils of the patient, respectively, when the bodyportion is in a second orientation, so as to communicate the first fluidpath with the right nostril and the second fluid path to the leftnostril.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate withtwo fluid paths. A pair of nostril interfaces project from the bodyportion. An oral sampler portion is operatively joined to the bodyportion and has an orifice configured to communicate with at least oneof the fluid paths. The oral sampler portion comprises an adjustablestructure that enables an orientation of the orifice of the oral samplerportion to be changed and retained in different positions.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate with atleast one fluid path. An adjustable nostril interface is operativelyconnected to the body portion. The nostril interface is configured to bereceived by a nostril of the patient's nose and in communication withthe fluid path. The nostril interface comprises an adjustable structureto enable a length and/or orientation of the nostril interface to beadjustable relative to the body portion.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate with atleast one fluid path. A nostril interface is operatively connected withthe body portion to communicate the fluid path with a nostril. Anattachment device is constructed and arranged to attach the body portionto the nose of a patient. The attachment device includes a nose engagingportion connected with the device for engaging an external surface ofthe patient's nose.

In another embodiment, this object is achieved by providing a patientinterface that includes a tubing defining a fluid path, the tubinghaving an orifice at one end of the fluid path and through which a fluidis communicated from or to a patient. A body portion comprises a tubingholder portion that is constructed and arranged to secure a portion ofthe tubing that is spaced from the orifice for positioning the orificeto communicate the fluid path with the patient. A mounting structure isprovided for mounting the body portion to the head of the patient.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate with afluid path. At least a section of the body portion is inflatable by afluid. A nostril interface extends from the body portion and isconstructed and arranged to communicate a nostril of a patient with thefluid path.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate with afluid path. A nostril interface and at least one attachment portionextends from the body portion. An adhesive is provided on the attachmentportion to removably attach the attachment portion to a patient's face.

In another embodiment, this object is achieved by providing a patientinterface that includes a first nostril interface configured to beinserted into a first nostril of a patient and comprising a firstconduit for communicating with the first nostril of the patient. Asecond nostril interface is configured to be inserted into a secondnostril of the patient and comprising a second conduit for communicatingwith the second nostril of the patient. The first nostril interface iscapable of relative sliding movement with respect to the second nostrilinterface to enable an adjustment of spacing therebetween.

In another embodiment, this object is achieved by providing a patientinterface that includes an integrally formed structure including (1) atubing portion defining first and second fluid paths, and (2) anappliance portion that includes a first nostril interface thatcommunicates with the first fluid path, and a second nostril interfacethat communicates with the second fluid path.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate with afluid path. A nostril interface in communication with the fluid pathextends from the body portion. A securement portion also extends fromthe body portion. The securement portion is disposed proximate thenostril interface and engages an exterior surface of the patient's nose.The nostril interface and the securement portion are cooperable to clampa portion of the patient's nose therebetween.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion configured to communicate with afluid path. A nostril interface extends from the body portion and is incommunication with the fluid path. A securement portion extends from thebody portion. The securement portion is disposed proximate the nostrilinterface and comprises two clamping portions for clamping a portion ofthe patient's nose therebetween.

In another embodiment, this object is achieved by providing a patientinterface that includes a head mount configured to be secured on thehead of a patient. The head mount includes a docking portion constructedand arranged to be disposed proximate to the nose of the patient. Anappliance is provided to be removably attached to the docking portion.The appliance portion includes a nostril interface for communicating afluid path to the nostril of the patient.

In another embodiment, this object is achieved by providing a patientinterface that includes a body portion having a first passage configuredto communicate with a first fluid path that withdraws a first fluid froma patient. A second passage is configured to communicate a with a secondfluid path that supplies a second fluid to the patient. A nostrilinterface extends from the body portion and is configured to be receivedby a nostril of the patient's nose. The nostril interface has a firstorifice that communicates with the first passage of the body portion toreceive the first fluid from the patient. A second orifice communicateswith the second passage of the body portion to output the second fluidto the patient.

In another embodiment, this object is achieved by providing a nostrilinterface configured to be inserted into a nostril of a patient. Thenostril interface includes an inner conduit extending through thenostril interface. The inner conduit is configured to receive a firstfluid from the nostril of the patient. An outer conduit surrounds atleast a portion of the inner conduit. The outer conduit is configured tosupply a second fluid to the nostril of the patient. A moistureexchanger is configured to receive moisture from the first fluid and tosupply the moisture to the second fluid.

In another embodiment, this object is achieved by providing a patientinterface that includes a fluid delivery conduit configured to deliver afirst fluid to at least one nostril of a patient. A nasal interfacecomprising a pair of nostril interfaces is configured to be insertedinto the nostrils of the patient for receiving a second fluid from thepatient. The fluid delivery conduit is movable relative to the nostrilinterface, wherein delivery of the first fluid to the at least onenostril of the patient is controlled by the position of the fluiddelivery conduit relative to the nasal interface such that 1) when thefluid delivery conduit is in a first position relative to the nasalinterface, the fluid delivery conduit is configured to deliver the firstfluid to both nostrils of the patient; and 2) when the fluid deliveryconduit is in a second position relative to the nasal interface, thefluid delivery conduit is configured to deliver the first fluid to oneof the nostrils of the patient.

In another embodiment, this object is achieved by providing a patientinterface that includes a fluid delivery conduit having output openingsconfigured to deliver a first fluid to the nose of a patient. A pair ofnostril interfaces are configured to be inserted into the nostrils ofthe patient for receiving a second fluid from the patient. The fluiddelivery conduit is capable of relative movement with respect to thenostril interfaces that adjusts the output openings to generally controla relative amount of the first fluid being directed to the first nostrilof the patient in comparison with amount of the first fluid directed tothe second nostril of the patient.

In another embodiment, this object is achieved by providing a patientinterface that includes an appliance portion including a nostrilinterface configured to be received by a patient's nostril and toprovide fluid communication between the nostril and a fluid path. Aphysiological function sensor is connected with the appliance portionfor engagement with the skin of the nose of the patient and generating asignal based upon a physiological function measurement.

Another aspect of the present invention provides patient interfaces,such as gas sampling cannulas, with selective nostril oxygen delivery,so that the oxygen can be preferentially directed to either or bothnostrils.

Another aspect of the present invention provides a patient interfacethat provides primary and secondary detection of the respiratorycondition of the patient.

A further aspect of the present invention provides an apnea monitor inwhich the primary and secondary detection signals or collected at asingle site on the patient.

A further aspect of the present invention provides a single siteambulatory sleep diagnostic sensor that provides measures of effort(such as respiratory effort), SpO₂, and flow.

These and other aspect, features, and characteristics of the presentinvention, as well as the methods of operation and functions of therelated elements of structure and the combination of parts and economiesof manufacture, will become more apparent upon consideration of thefollowing description and the appended claims with reference to theaccompanying drawings, all of which form a part of this specification,wherein like reference numerals designate corresponding parts in thevarious figures. It is to be expressly understood, however, that thedrawings are for the purpose of illustration and description only andare not intended as a definition of the limits of the invention. As usedin the specification and in the claims, the singular form of “a”, “an”,and “the” include plural referents unless the context clearly dictatesotherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a patient interface forgas sampling, supplemental gas delivery, or combined gas sampling andsupplemental gas delivery;

FIG. 2 is a more detailed view of an embodiment of the interface of FIG.1;

FIG. 3 is a more detailed view of another embodiment of the interface ofFIG. 1;

FIG. 4 is a perspective view of another embodiment a patient interfacefor gas sampling, supplemental gas delivery, or combined gas samplingand supplemental gas delivery;

FIG. 5 is a more detailed view of an embodiment of the interface of FIG.4;

FIG. 6 is a perspective view of another embodiment of the interface ofFIG. 4

FIG. 7 is a perspective view of another embodiment of the interface ofFIG. 4;

FIG. 8 is a detailed view of another embodiment of the interface of FIG.7;

FIG. 9 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 10 is a more detailed view of one side of the interface of FIG. 9;

FIG. 11 is a more detailed view of the interface of the interface ofFIG. 9;

FIG. 12 is a perspective view of another embodiment of the interface ofFIG. 9;

FIG. 13 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 14 is a side view of the interface of FIG. 13;

FIG. 15 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 16 is a more detailed view of the interface of FIG. 15;

FIG. 17 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental oxygen gas, or combined gassampling and supplemental gas delivery;

FIG. 18 is a more detailed view of the interface of FIG. 17;

FIG. 19 is a detailed view of another embodiment of the interface ofFIG. 17;

FIG. 20 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 21 is a more detailed view of the interface of FIG. 20;

FIG. 22 is a cross-sectional view of another embodiment of a patientinterface for carbon dioxide sampling, supplemental oxygen delivery, orcombined carbon dioxide sampling and supplemental oxygen delivery;

FIG. 23 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 24 is a cross-sectional view of a tubing portion of the interfaceof FIG. 23;

FIG. 25 is a schematic cross-sectional view of an appliance portion ofthe interface of FIG. 23;

FIG. 26 is a more detailed view of a distal end of a nostril interfaceof the patient interface of FIG. 23;

FIG. 27 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery from or to a single nostril;

FIG. 28 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 29 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery from or to a single nostril;

FIG. 30 is a cross-sectional view of a tubing portion of the interfaceof FIG. 29;

FIG. 31 is a schematic cross-sectional view of an appliance portion ofthe interface of FIG. 29;

FIG. 32 is a more detailed view of a nostril interface of the patientinterface of FIG. 29;

FIG. 33 is a perspective view of an embodiment of a nostril interfacefor combined gas sampling and supplemental gas delivery;

FIG. 34 is a perspective view of another embodiment of a patientinterface for gas sampling, supplemental gas delivery, or combined gassampling and supplemental gas delivery;

FIG. 35 is a cross-sectional view of an embodiment of nasal interfaceportion of a patient interface for combined gas sampling andsupplemental gas delivery;

FIG. 36 is a perspective view of an embodiment of a fluid deliveryconduit of a patient interface for combined gas sampling andsupplemental gas deliver;

FIG. 37 is a perspective view of a patient interface for combined gassampling and supplemental gas delivery that includes the nasal interfaceportion of FIG. 35 and an embodiment of the fluid delivery conduit ofFIG. 36 with the fluid delivery conduit in a first position relative tothe nasal interface;

FIG. 38 is a more detailed view of one end of the patient interface ofFIG. 37;

FIG. 39 is a perspective view of the patient interface of FIG. 37 withthe fluid delivery conduit in a second position relative to the nasalinterface;

FIG. 40 is a perspective view of the patient interface of FIG. 37 withthe fluid delivery conduit in a third position relative to the nasalinterface;

FIG. 41 is a perspective view of another embodiment of the patientinterface of FIG. 1;

FIG. 42 is a front view of another embodiment of the patient interfaceof FIG. 41;

FIG. 43 is a front view of another embodiment of the patient interfaceof FIG. 42;

FIG. 44 is a back view of another embodiment of the patient interface ofFIG. 10;

FIG. 45 is a back view of another embodiment of the patient interface ofFIG. 44;

FIG. 46 is a perspective view of another embodiment of the patientinterface of FIG. 13;

FIG. 47 is a side view of another embodiment of the patient interface ofFIG. 46;

FIG. 48 is a perspective view of another embodiment of the patientinterface of FIG. 21;

FIG. 49 is a perspective view of another embodiment of the patientinterface of FIG. 27;

FIG. 50 is a perspective view of another embodiment of the patientinterface of FIG. 49;

FIG. 51 is a block diagram of an embodiment of an apnea monitor;

FIG. 52 is perspective view of an embodiment of the apnea monitor ofFIG. 51;

FIG. 53 is a flow diagram of a method for monitoring apnea.

FIG. 54 is a perspective view of an embodiment of a patient interfacefor gas sampling from a single nostril and supplemental gas delivery;

FIG. 55 is a cross-sectional view of a tubing portion of the interfaceof FIG. 54; and

FIG. 56 is a perspective view of a strap that is configured to bereceived by an ear of the patient.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 illustrates a patient interface 10 according to an embodiment ofthe present invention. Patient interface 10 may be used as a combinationoral and nasal gas sampling cannula or “appliance,” and/or may also beused as supplemental gas delivery cannula or “appliance.” Typically, thesample gas is carbon dioxide (CO₂) and/or oxygen (O₂) and thesupplemental gas is oxygen (O₂). However, the present inventioncontemplates that the sampled gas can be any gas or combination of gascapable of being measured using any existing techniques. The presentinvention also contemplates that the supplemental gas can be any gas orcombination of gas, such as helium, nitrogen, a helium-oxygen mixture(heliox), or a nitrogen-oxygen mixture.

As used herein, the term “patient interface” is intended to referbroadly to any device or structure that interfaces or cooperates with apatient, or has a portion thereof that interfaces or cooperates with apatient. The term “appliance” broadly refers to any device or structurethat outputs a fluid to and/or intakes a fluid from a patient. The term“cannula” as used herein refers one type of “appliance” and refers, morespecifically, to a structure that has at least a portion thereof thatprotrudes at least partially into at least one nostril of a patient.

As shown, patient interface 10 includes a body portion 12 configured tocommunicate with at least one fluid path. In the illustrated embodiment,a first fluid path 14 and a second fluid path 15 are provided by tubing11 and 16, respectively. The term “tubing” as used herein is intended torefer to a flexible, rigid, or semi-rigid tube. Of course any suitablestructure for transporting fluids may be configured to define the fluidpaths.

The present invention contemplates that at least one fluid pathcommunicates the sample gas to a suitable device for measurement, suchas a gas analyzer, pressure sensor, flow sensor, temperature sensor,humidity sensor, etc. In the case of gas analyzer, the sample gas istransported to the measurement site. In the case of a pressure or flowmeasurement, the fluid path communicates the gas a suitable pressure orflow sensing device. Other sensors measuring other properties orcomponents of the fluid, such as temperature, humidity, and gascomposition, fluid or optical communication with the fluid path arecontemplated as well.

In the illustrated embodiment, body portion 12 has a pair of tubingconnecting portions 17 and 19 for interfacing and/or connecting withfluid paths 14 and 15, respectively. In one embodiment, connectingportions 17 and 19 comprise respective orifices in body portion 12,which orifices each have an inner diameter configured to form a frictionfit with the outer diameter of an associated tubing 11, 16,respectively.

Other mechanisms for forming connections between body portion 12 and thetubing or fluid paths are possible. For example, the connecting portionson body portion 12 may be in the form of projections, each containing apassage therein and having an outer surface with an outer diameterconfigured to form a friction fit with the inner diameter of anassociated one of the tubes, etc. In other embodiments, the connectionmay be achieved by an adhesive or other joining structure. In anotherembodiment, the tubing and the body portion may be integrally formed.The disclosed embodiments are not intended to be limiting in any way.

As shown in the embodiment of FIG. 1, tubing 11 and 16 of patientinterface 10 are configured to extend from body portion 12 and at leastpartially around each ear of the patient to hold body portion 12 in agenerally stable position relative to the nose of the patient. Therouting of tubing 11, 16 around each ear of the patient is only oneexample of how the body portion may be held in a generally stableposition relative to the nose of the patient. For example, in anotherembodiment, tubing 11, 16 may be routed from body portion 12 over thehead of the patient, and secured in a variety of ways known in the art,including but not limited to clips, adhesives, etc. The illustratedembodiment is not intended to be limiting in any way.

Patient interface 10 also includes at least one generally tubularnostril interface 18 that projects from the body portion 12. In theillustrated embodiment, two nostril interfaces 18 and 21 are shown.Although it is contemplated that in some embodiments, only one nostrilinterface 18 may be provided. Nostril interfaces 18 and 21 areconfigured to be inserted into an associated nostril of a patient andhave respective internal orifices in communication with associated fluidpaths 14 and 15, respectively.

As shown in FIG. 2, communication between nostril interface 18 and theorifice of connecting portion 17 is provided by an internal conduit 23within body portion 12. Similarly, an internal conduit 25 communicatesnostril interface 21 with connecting portion 19, as known in the art.This allows fluid paths 14 and 15 to be in fluid communication with thenostrils, so that fluids may either be received from the patient and/orsupplied to the patient. In one embodiment, nostril interface 18,connecting portion 17, and fluid path 14 may be configured to supply afluid that includes oxygen (O₂) to the patient from a suitable fluidsupply, and nostril interface 21, connecting portion 19, and fluid path15 may be configured to receive a fluid that includes carbon dioxide(CO₂) expired from the patient. In such an embodiment, fluid path 15communicates the carbon dioxide to a suitable device, such as a gasanalyzer, so that the concentration of the carbon dioxide in the expiredfluid and/or rate of flow of the expired fluid may be monitored overtime. In such an embodiment, an internal wall structure 24 sealsinternal conduit 23 communicating with nostril interface 18 frominternal conduit 25 communicating with nostril interface 21. In oneembodiment, this internal wall structure is formed in accordance withthe teachings of U.S. Pat. No. 5,335,656, which is hereby incorporatedby reference in its entirety.

It should also be appreciated that while fluid path 14, connectingportion 17, and nostril interface 18 are mentioned above in oneembodiment as being used for oxygen delivery, while fluid path 15,connecting portion 19, and nostril interface 21 are mentioned as beingused for carbon dioxide sampling, these may be reversed depending onwhich nostril (left or right) is preferred for carbon dioxide samplingversus oxygen delivery.

In another embodiment, nostril interfaces 18, 21 and associated fluidpaths 14, 15 all receive a fluid that includes carbon dioxide from thepatient. In another embodiment, nostril interfaces 19, 21 and associatedfluid paths 14, 15 all deliver oxygen to the patient.

Nostril interface 18 and/or 21 may be in the form of a projection ortruncated prong that is constructed and arranged to extend into thenostril. The length of the prong may vary and may depend on the size ofthe nostrils of the patient. For example, the prong may be shorter for achild patient and longer for an adult patient. In addition, nostrilinterface 18 and/or 21 may be shaped or angled relative to body portion12 so as to substantially conform with the nostril, which may makeinterface 10 more comfortable for the patient to wear.

As shown in FIG. 1, patient interface 10 in one embodiment may alsoinclude an oral sampler 20 that is on a side of body portion 12 oppositethe nostril interfaces 18, 21 and projects from the body 12 in adirection opposite the nostril interfaces 18, 21. Oral sampler 20 isconfigured to receive a fluid from the mouth of the patient. Oralsampler 20 has an opening 27, or sampling inlet, that can be positionednear the patient's mouth so that when the patient exhales, oral sampler20 may communicate a portion of the fluid containing carbon dioxidebeing exhaled from the patient to the appropriate sampling fluid pathleading to the suitable testing device, such as a gas analyzer. Oralsampler 20 may include a collector (not shown) that is configured todirect the expired gases from the patient's mouth to opening 27. Such acollector is shown in FIG. 10 and described in further detail below.

In one embodiment shown in FIG. 3, oral sampler 20 includes an internalpassageway or conduit 29 that connects opening 27 in oral sampler 20with internal conduit 25 leading to connecting portion 19 so that fluidbeing exhaled by one nostril and the mouth may enter fluid path 15 andbe transmitted to the gas analyzer. As illustrated in the embodiment ofFIG. 3, internal conduit 23 only communicates fluid path 14 with one ofnostril interfaces 18. Internal conduits 23, 25, and 29 should havesmooth surfaces and should be sized and shaped so as to minimize gasmixing and maintain the fidelity of the gas waveform.

In an embodiment, oral sampler 20 is configured to be adjustablerelative to body portion 12 so that opening 27 in oral sampler 20 may beoptimally positioned relative to the patient's mouth to account fordifferences in anatomy as well as flow direction from the patient's oralcavity, i.e. mouth. The adjustability may be provided to oral sampler 20with suitable materials and/or structures. For example, in oneembodiment, oral sampler 20 may be made from a flexible material, suchas a polymer or elastomeric material, that has an internal malleablematerial, such as a metal wire 31, so that opening 27 may be moved toand retained at the desired position relative to the patient's mouth.The wire may be embedded in the flexible material, or the wire may beattached to the flexible material on an outside surface thereof, asdescribed in greater detail in another embodiment below, which is herebyincorporated by reference.

Adjustability may also be provided by a bellows or accordion-likestructure in oral sampler 20, as described in greater detail in anotherembodiment below, which is hereby incorporated by reference. In oneembodiment, oral sampler 20 may be adjusted so that it is inoperative,i.e., unable to communicate the fluid being exhaled from patient throughthe mouth. This may be done by either positioning opening 27 to alocation that will not receive the fluid being exhaled by the patient,or in another embodiment, it may be done by crimping oral sampler 20 sothat passageway 29 is pinched off. In yet another embodiment, a separateor tethered plug or seal structure may be inserted into or covered overopening 27 to prevent exhaled fluid from entering opening 27.

In the embodiment of FIGS. 1-3, patient interface 10 also includes apair flexible stabilizers 22 or wings that extend laterally outwardlyfrom body portion 12 on opposite sides of body portion 12, as shown inFIG. 1. Specifically, each stabilizer 22 extends laterally outwardlyfrom an associated one of connecting portions 17, 19. As shown, eachstabilizer 22 has a concave-convex cross-section forming a portion of atubular configuration, and transitions into a complete tubularconfiguration that forms the connecting portions 17, 19. Stabilizers 22are made from a sufficiently low durometer material to substantiallyconform to the patient's adjacent facial surface when interface 10 ismounted to the patient. Stabilizers 22 extend away from body portion 12and provide an ergonomic configuration to enhance patient comfort. Inaddition, stabilizers 22 are sized to work in tandem with fluid paths14, 15 to hold the nostril interfaces 18, 21 in a substantially stableposition. Fluid paths 14, 15 may be positioned across stabilizers 22 andapply supportive force to the stabilizers when interface 10 is mountedto the user.

In an exemplary embodiment, interface 10 is manufactured from a soft(low durometer) material for a more comfortable fit for the patient. Forexample, the material of the interface may have a Shore A hardness ofabout 10 to about 40, and may be manufactured, for example, from apolyurethane or a silicone. In one embodiment, body portion 12,stabilizers 22, nostril interfaces 18, 21, and oral sampler 20 aremolded from the same material. In another embodiment, body portion 12and stabilizers 22 are molded from the same material, while nostrilinterfaces 18, 21 and oral sampler 20 are molded from a differentmaterial.

As indicated above, interface 10 illustrated in FIG. 1 may be used as acombination oral and nasal carbon dioxide sampling device, and/or mayalso be used as an oxygen delivery device. Depending on how fluid paths14, 15 and internal conduits 23, 25 are configured, interface 10 may beconfigured to provide carbon dioxide sampling from one nostril interfaceand oxygen delivery to the other nostril interface, or both nostrilinterfaces may be used for carbon dioxide sampling. In an embodiment,the nostril interfaces may be configured to provide carbon dioxidesampling from as well as oxygen delivery to both nostrils.

It should be appreciated that the features of interface 10 discussedabove may also be used in the embodiments of the patient interfacesdiscussed below. Thus, the features and attributes discussed above arehereby incorporated by reference into each of the other embodimentsdiscussed below.

FIG. 4 illustrates a patient interface 30 according to a furtherembodiment of the invention. Interface 30 includes a body portion 32that is configured to communicate with a first fluid path 33 and asecond fluid path 34. A first nostril interface 35 and a second nostrilinterface 36 extend from a first side 37 of body portion 32 and areconfigured to be inserted into the nostrils of the patient when the bodyportion is in a first orientation (shown in FIG. 4). First nostrilinterface 35 communicates with the first fluid path 33 and the secondnostril interface communicates with second fluid path 34. Interface 30also includes a third nostril interface 38 and a fourth nostrilinterface 39 that extend from a second side 40 of body portion 32. Thethird nostril interface also communicates with first fluid path 33, andfourth nostril interface 39 communicates with second fluid path 34.Third nostril interface 38 and fourth nostril interface 39 areconfigured to be inserted into the nostrils of the patient when bodyportion 32 is in a second orientation, which is an orientation that is180° from the first orientation of FIG. 4, and shown in FIG. 5.

Specifically, when interface 30 is in the first orientation, firstnostril interface 35 is configured to be inserted into the left nostrilof the patient, and second nostril interface 36 is configured to beinserted into the right nostril of the patient, so as to communicatefirst fluid path 33 with the left nostril and second fluid path 34 withthe right nostril. Conversely, when interface 30 is in the secondorientation, shown in FIG. 5, third nostril interface 38 is configuredto be inserted into the right nostril, and fourth nostril interface 39is configured to be inserted into the left nostril, so as to communicatefirst fluid path 33 with the right nostril, and second fluid path 34with the left nostril.

As shown, interface 30 is symmetrically configured so that it may beused when body portion 32 is either in the first or second orientation.When body portion 32 is in the first orientation, third nostrilinterface 38 and fourth nostril interface 39 are configured to bepositioned near the patient's mouth so as to communicate first fluidpath 33 and second fluid path 34 with the patient's oral cavity.Conversely, when body portion 32 is in the second orientation, firstnostril interface 35 and second nostril interface 36 are configured tobe positioned near the patient's mouth so as to communicate second fluidpath 34 and first fluid path 33 with the patient's oral cavity.

In an exemplary embodiment, as shown in FIG. 5, all of the nostrilinterfaces 35, 36, 38, 39 may be angled relative to body portion 32 soas to allow nostril interfaces 35, 36, 38, 39 to conform to the nostrilsfor a more comfortable fit on the patient, as well as be directedtowards the patient's mouth when in the respective orientation. Inaddition, body portion 32 may be provided with a slightly concavesurface on a side thereof as it extends laterally for engaging thesurface area of skin beneath the patient's nose. This concave surfaceengages the surface area of skin beneath the patient's nose irrespectiveof whether body portion 32 is in the first or second orientation, andprovides a comfortable engagement with the patient.

As shown in FIG. 5, first fluid path 33 and second fluid path 34 aredefined by tubing 41, 42, respectively, each of which are received bybody portion 32 on opposite ends of the body portion at a firstconnecting portion 43 and a second connecting portion 44, respectively.As shown, first connecting portion 43 includes an orifice 45 that isconfigured to receive tubing 41. The diameter of orifice 45 may be equalto or slightly less than the outer diameter of tubing 41 so that a sealmay be formed between body portion 32 and tubing 41. Likewise, secondconnecting portion 44 includes an orifice 46 that is configured toreceive tubing 42 in a similar manner. Like the embodiment illustratedin FIG. 1, tubing 41, 42 may be flexible enough to extend from bodyportion 32 and at least partially around each ear of the patient to holdbody portion 32 in a fixed position relative to the patient's nose. Thefixed position may be the first orientation, in which first nostrilinterface 35 and second nostril interface 36 are positioned in thenostrils, or the fixed position may be the second orientation, in whichthird nostril interface 38 and fourth nostril interface 39 arepositioned in the nostrils.

As illustrated in FIG. 5, and as can be appreciated from the discussionrelating to the embodiment of FIG. 1, body portion 32 may include aseparator or seal 47 that separates a first conduit 48, or passageway,from a second conduit 49, or passageway within the body portion 32.First conduit 48 is configured to communicate a fluid between firstnostril interface 35, third nostril interface 38, and first connectingportion 43, and second conduit 49 is configured to communicate a fluidbetween second nostril interface 36, fourth nostril interface 39, andsecond connecting portion 44.

In one exemplary embodiment, first fluid path 33 and second fluid path34 are both configured to communicate a fluid containing carbon dioxidethat is being exhaled by the patient to a suitable testing device, suchas a gas analyzer. That is, all four nostril interfaces 35, 35, 38, 39may be configured to communicate carbon dioxide from the patient (viathe mouth and the nose) to first and second fluid paths 33 and 34. Inanother embodiment, first fluid path 33 and nostril interfaces 35, 38are configured to communicate the fluid being exhaled by the patient tothe gas analyzer, while second fluid path 34 and nostril interfaces 36,39 are configured to supply oxygen to the patient for inhalation.Because the flow from the patient's nostrils is usually not equal andoften dramatically different (sometimes greater than an order ofmagnitude difference), a symmetrical design would allow the interface 30to be “flipped,” thereby permitting carbon dioxide sampling from eitherof the patient's nostrils and oxygen delivery to other nostril.

In yet another embodiment, first fluid path 33 and second fluid path 34,and all four nostril interfaces 35, 36, 38, 39 are configured tocommunicate oxygen to the patient for inhalation.

In an embodiment, as shown in FIG. 6, which is a modified version ofpatient interface 30 of FIG. 5, patient interface 30 also includes afirst flexible stabilizer 50 and a second flexible stabilizer 51 thattake the form of tubular portions extending from body portion 32 onopposite sides of the body portion. Although not fully shown, secondstabilizer 51 is of the same design as first stabilizer 50. Like thestabilizers shown and discussed above with respect to the embodimentillustrated in FIG. 1, stabilizers 50, 51 may be configured tosubstantially conform to the patient's face when the interface 30 ismounted to the patient.

In the illustrated exemplary embodiment, stabilizers 50, 51 have asubstantially closed tubular cross-sectional configuration. In addition,first connecting portion 43 is part of first stabilizer 50 and islocated at a distal end of the first stabilizer, and second connectingportion 44 is part of second stabilizer 51 and is located at a distalend of the stabilizer. Tubing 41, 42 is configured to connect to therespective connecting portion 43, 44, and extend from each ofstabilizers 50, 51 and at least partially around each ear of the patientto hold body portion 32 in a fixed position relative to the nose.

FIG. 7 illustrates another embodiment of patient interface 30 of FIG. 6.As shown, connecting stabilizers 50, 51 (51 being of the same design as50) have a similar function and purpose as stabilizers 22 shown in FIGS.1-3. As shown, stabilizers 50, 51 each have a flattened configurationthat widens into a rounded distal end portion so as to form a generallyteardrop shape. First connecting portion 43 is located at anintermediate section of first stabilizer 50, as illustrated in FIG. 7,and second connecting portion 44 is located at an intermediate sectionof second stabilizer 51 (not shown).

Patient interface 30 also includes a modified structure for mounting thepatient interface to the head of the patient. Specifically, in thisembodiment, patient interface 30 incorporates a head mount or headgearthat includes a first strap 52 connected to first stabilizer 50 at thedistal end of first stabilizer, and a second strap (not shown) connectedto second stabilizer 51 at the distal end thereof. For illustrativepurposes, only first strap 52 will be discussed, although it should beappreciated that the same would apply to the second strap as well.

Strap 52 is configured to extend from first stabilizer 50 and at leastpartially around the ear of the patient to hold body portion 32 in astable or fixed position relative to the patient's nose. As shown inFIG. 7, in this embodiment, strap 52 has a closed loop 52 a at a distalend thereof. Closed loop 52 a is dimensioned to have an inner diameterof substantially the same dimension as the outer diameter of the tubing41. Tubing 41 extends from first stabilizer 50, and strap 52 isconfigured to receive tubing 41 so as to guide the tubing fromstabilizer 50 and away from the patient. While in the illustratedembodiment tubing 41 is received by strap 52 at a distal end thereof,such a configuration is not intended to be limiting in any way. Forexample, tubing 41 may be received by strap 52 at an intermediateportion thereof.

In an embodiment, body portion 32 may also include an adjustor 53located between first nostril interface 35 and second nostril interface36, as well as between third nostril interface 38 and fourth nostrilinterface 39, as shown in FIG. 7. Adjustor 53 is configured to adjust aposition of first nostril interface 35 relative to second nostrilinterface 36 and a position of third nostril interface 38 relative tofourth nostril interface 39. In an embodiment, adjustor 53 is a flexiblesection of the body portion 32. In one embodiment, the flexible sectionmay comprise bellows 54, or any other accordion-like structure thatallows body section 32 to lengthen, shorten, or bend, and retain thelengthened, shortened, or bent configuration. Such accordion or bellowsstructures are known, for example, from commonly available plasticdrinking straws. Adjustor 53 allows for patient interface 30 to beadjusted for the anatomic variations seen between different aged andsized subjects, thereby providing a more comfortable fit for a largerpopulation of patients.

As shown in FIG. 8, patient interface 30 may also include at least oneseal or plug structure 55 configured to block fluid communication with(i.e., to and from) at least one of nostril interfaces 35, 36, 38, 39.Seal structure 55 may be a plug that is received by an orifice 56 of anyone of nostril interfaces 35, 36, 38, 39, or seal structure 55 may be acap that frictionally engages an outside surface of any one of thenostril interfaces, or vice-versa. It is also contemplated that the capmay be of a twist-off design that has threads on an inner surfacethereof that match threads on the outside surface of the nostrilinterface. In the illustrated embodiment, one seal structure 55 isconnected to each nostril interface 35, 36, 38, 39 so as to block fluidcommunication with all of the nostril interfaces. In one embodiment, thefour seal structures 55 blocking each nostril interface 35, 36, 38, 39may be integrally molded with the associated nostril interface and maybe selectively broken, cut, or snapped off by the clinician, as desired.Of course, the clinician may block fluid communication with differentcombinations of nostril interfaces 35, 36, 38, 39, or none at all. It iscontemplated that any other suitable seal structure for sealing off anostril interface may be used. The illustrated embodiment is notintended to be limiting in any way.

In one embodiment, for example, where nostril interface 35 deliversoxygen to one nostril and nostril interface 36 receives carbon dioxidefrom the other nostril, nostril interface 39 may remain open to functionas an oral sampling port, while nostril interface 38 may be sealed byseal structure 55. This may be done to increase the amount of oxygendelivered to the nostril through nostril interface 35 in comparison witha configuration in which nostril interface 38 is left unsealed.

FIG. 9 illustrates a patient interface 60 that includes an oral andnasal cannula or appliance that is configured to sample gas, such ascarbon dioxide, and/or supply gas, such as oxygen, to the patient. Asshown, patient interface 60 includes a body portion 62 that isconfigured to receive a first fluid path 61 and a second fluid path 63.A first nostril interface 64 and a second nostril interface 65 projectfrom a top surface 66 of the body portion 62. Nostril interfaces 64, 65are configured to be aligned with the patient's nostrils when patientinterface 60 is mounted on the patient. Nostril interfaces 64, 65provide fluid communication between the nostrils and associated fluidpaths 61, 63.

Top surface 66 of body portion 62 is configured to have a slightlyconcave surface so as to provide a gap between the top surface 66 andthe lower skin between the nostrils so that the patient's nostrils arenot sealed by body portion 62, but rather allows fluid communicationbetween the nostrils and the atmosphere outside of the patient interface60 with minimum restriction of the flow in and out of the nostrils.Although nostril interfaces 64, 65 are illustrated as “stubs,” it isalso contemplated that in other embodiments, the nostril interfaces maybe longer and shaped to follow the natural curvature of the interior ofthe nostril, as shown and described in other embodiments herein. Theillustrated embodiment is not intended to be limiting in any way.

As illustrated, patient interface 60 also includes an oral samplerportion 67 that is operatively joined to the body portion 62 and extendsfrom body portion 62 in a direction away from nostril interfaces 64, 65.Oral sampler portion 67 has an orifice 68 that is configured tocommunicate with at least one of fluid paths 61, 63. Orifice 68 isconfigured to receive a fluid being exhaled from the oral cavity throughthe mouth of the patient or, in a different embodiment, to deliver afluid, such as oxygen, for the patient to inhale.

As illustrated in FIG. 10, oral sampler portion 67 includes a collector80 on a distal end thereof that is configured to direct the expiredgases from the patient's mouth to orifice 68. Collector 80 may be shapedas a scoop or any other shape that would direct the flow in a smoothmanner, while minimally disturbing and mixing the flow. In theillustrated embodiment, collector 80 includes a concave surface 81 thatis shaped so as to generally direct the flow of expired gases thatengage surface 81 towards opening 68. The illustrated embodiment is notintended to be limiting in any way.

Oral sampler portion 67 is formed from a malleable structure thatenables an orientation of orifice 68 of oral sampler portion 67 to bechanged and retained in different positions. In other words, oralsampler portion 67 may be configured to be adjustable relative to themouth of the patient. In an embodiment, oral sampler portion 67 includesat least one malleable wire 70 that is configured to provideadjustability to the shape of the oral sampler portion. By bending wire70, orifice 68 in the oral sampler portion 67 may be moved relative tobody portion 62, retain the adjusted position, to position the oralsampler portion as desired relative to the mouth of the patient whenpatient interface 60 is mounted to the patient. In an exemplaryembodiment, wire 70 generally retains the shape to which it is bent, andmay be embedded in oral sampler portion 67. In another embodiment, twomalleable wires 70 and 71 may be disposed on opposing outside surfaces72 a, 72 b of oral sampler portion 67, respectively, as shown in FIGS.10 and 11.

In a further exemplary embodiment, body portion 62, nostril interfaces64, 65, and oral sampler portion 67 are molded from a single piece ofmaterial. The material may be any suitable material that fully complieswith the applicable regulations for such interface devices. For example,patient interface 60 may be molded from soft biocompatible materials,such as polyurethanes and silicones.

Fluid paths 61, 63 may be defined by suitable tubing 73, 74,respectively, that extends from body portion 62 and at least partiallyaround each ear of the patient to hold the body portion in a fixedposition relative to the nose of the patient. “Suitable” tubing isdefined as tubing that complies with the applicable regulations forinterface devices. Tubing 73, 74 should be sized such that kinks thatwould impede flow of the fluids in fluid paths 61, 63 are difficult toform. Tubing 73, 74 may be connected to the body portion 62 in anymanner as described above.

Also shown in FIG. 9 is an adjustor 75 for adjusting or controlling thetension provided to tubing 73, 74 and body portion 62 so body portion 62will stay in a fixed position relative to the patient's nose. Asillustrated, adjustor 75 is in the form of an adjustable slide and isconfigured to slidingly receive tubing 73, 74 coming from each ear at aposition below the chin of the patient. Adjustor 75 includes twopassages 76, 77 that are configured to provide a frictional interfacewith the tubing 73, 74, respectively, so as to provide frictionalresistance when the adjustor is slid relative to tubing 73, 74. Ofcourse, other configurations of adjustors may be used. The illustratedembodiment is not intended to be limiting in any way.

As shown in FIG. 12, body portion 62 may also include a malleablestructure 78 that interconnects nostril interfaces 64, 65 to enable adistance between the nostril interfaces to be adjustable. In anembodiment, malleable structure 78 includes a malleable wire 79. Wire 79may be constructed and arranged in a bellows-like structure, wherein thewire is bent in a serpentine-like pattern, as illustrated in FIG. 12. Inan embodiment, wire 79 may be an extension of wire 70 that is part ofthe sampler portion 68, as shown in FIG. 12. Wire 79 may be embedded inbody portion 62, or may be connected to body portion 62 on an outsidesurface of the body portion. Of course any suitable malleable structuremay be used to provide the adjustability to the distance between thenostril interfaces 64, 65. By providing malleable structure 78 to thebody portion 62, patient interface 60 may be adjusted for the anatomicvariations seen between different aged and sized subjects, therebyproviding a more comfortable fit for a large population of patients. Theillustrated embodiment is not intended to be limiting in any way.

FIGS. 13 and 14 illustrate another embodiment of a patient interface 90according to the principles of the present invention. Interface 90 maybe an oral and nasal gas sampling and/or gas delivery cannula orappliance. It is contemplated that this embodiment of patient interface90 may be particularly applicable for emergency medicine, as well asapplications that include procedural sedation. Patient interface 90includes a body portion 92 configured to communicate with at least onefluid path. In the embodiment shown, body portion 92 communicates withtwo fluid paths 91, 93, and an attachment device 94 is constructed andarranged to attach body portion 92 to the nose of the patient.Attachment device 94 includes a nose engaging portion 95 connected withbody portion 92 for engaging an external surface of the nose, as shownin FIG. 13.

Nose engaging portion 95 may include a spring clip 96 that isconstructed and arranged to engage opposite sides of the patient's nose.More specifically, the spring clip 96 may have a U-shaped configurationthat is configured to engage the bridge of the patient's nose, as shownin FIG. 13. The legs of the U-shaped configuration can be separated toreceive the bridge of the nose and be gently biased toward one anotherto grasp the nose therebetween. Attachment device 94 may additionally,or alternatively, include an adhesive 97 that is configured to beremovably attached to the patient's nose to assist in securing patientinterface 90 to the patient. Adhesive 97 may be any suitable adhesivethat will firmly hold attachment device 94 in place on the patient'snose, yet be easily removed upon application of suitable pressure. In anembodiment, adhesive 97 is located on spring clip 96 at portions of thespring clip that engage the patient's nose.

As shown in FIG. 13, two adjustable nostril interfaces 98, 99 areoperatively connected to body portion 92. Each nostril interface 98, 99is configured to be received by a nostril of the patient's nose and tobe in communication with fluid paths 91, 93. Nostril interfaces 98, 99each incorporate a malleable structure 100, 101, respectively, thatenables the length and/or orientation of nostril interfaces 98, 99 to beadjustable relative to body portion 92. In the illustrated embodiment,which should not be considered to be limiting in any way, malleablestructures 100, 101 include a bellows-like structure, similar to aflexible drinking straw, as mentioned previously. In another embodiment,the nostril interfaces may be a malleable tube or tubing that may beheld in place once the nostril interface is inserted in the one of thepatient's nostrils.

Body portion 92 is configured to be in communication with at least oneof the fluid paths 91, 93 via a junction 103. Junction 103 may be amalleable portion of body portion 92 or may be a malleable structurethat is connected to body portion 92 at one end thereof. Fluid paths 91,93 are defined by tubing 104, 105, respectively. One end of each tubing104, 105 is received by junction 103, and the other end of each tubing104, 105 may be connected to a fluid supplier or a fluid receiver. Forexample, one of fluid paths 91, 93 may communicate oxygen to one of thenostrils via the respective tubing 104, 105 and nostril interface 98,99, and other one of the fluid paths 91, 93 may communicate a fluid fromone of the nostrils via the respective tubing 104, 105 and nostrilinterface 98, 99. As may be appreciated in view of the description ofother embodiments, patient interface 90 may be configured to be asampling only, or a delivery only, or a combination sampling anddelivery patient interface.

Junction 103 is configured to provide an adjustment of the position oftubing 104, 105 relative to body portion 92 for improved tubingmanagement. For example, EMT's in an ambulance may want to route thetubing upwards and over the head, as illustrated. In other situations,the clinician may want to route the tubing to the side of the patient'shead, as shown by dashed lines 106 in FIG. 13.

In an embodiment, patient interface 90 also may include an oral sampler108 that is operatively connected to body portion 92 and is configuredto communicate with at least one of fluid paths 91, 93. Oral sampler 108includes an orifice 109 configured to sample a fluid exhaled from thepatient's mouth and/or supply oxygen to the patient mouth so that thepatient may inhale the oxygen. In an embodiment, oral sampler 108 mayinclude a malleable structure that allows for adjustment of the positionof orifice 109 relative to the mouth of the patient. The malleablestructure may include any of the structures discussed herein, such asmalleable wires, bellows, etc., may be incorporated into oral sampler108 to provide the adjustability.

FIG. 15 shows an embodiment of a patient interface 120 that may be usedas an oral and nasal gas sampling and/or gas delivery cannula orappliance. As illustrated, patient interface 120 includes a body portion122 that includes a tubing holder portion 123. In one embodiment, tubingholder portion 123 includes two networks of grooves 121 a, 121 b thateach includes a plurality of branches, although in an embodiment, onlyone groove that includes a plurality of branches may be provided.Grooves 121 a, 121 b are configured to receive tubing sections 124, 125,respectively, as shown in greater detail in FIG. 16. Each tubing section124, 125 defines a fluid path 126, 127, respectively, and each fluidpath 126, 127 is configured to communicate a fluid either being exhaledby the patient or inhaled by the patient, depending on the specificapplication, as can be appreciated from the previous discussion.

Tubing 124 has an orifice 128 at one end thereof, which coincides withone end of fluid path 126. Tubing holder portion 123 is constructed andarranged to secure a portion 129 of tubing 124 that is spaced fromorifice 128 for positioning the orifice to communicate fluid path 126with the patient, as shown in FIG. 15. Tubing 124 may be eitherpermanently affixed to tubing holder portion 123, or may be removablyreceived by the tubing holder portion so that they it may be removedfrom the tubing holder portion without damaging body portion 122. Groove121 a may be shaped and sized to complement the size of tubing 124. Forexample, groove 121 a may have a surface that is defined be a radiusthat is substantially the same as or slightly less that the outer radiusof tubing 124, so that tubing 124 may be frictionally fit with groove121 a without crimping the tubing.

As shown in FIG. 16, a vertical branch 129 of groove 121 a extends froma top surface 130 to a bottom surface 133 of tubing holder portion 123.Top surface 130 of tubing holder portion 123 is located near thepatient's nose, and bottom surface 133 is located near the patient'smouth when patient interface 120 is mounted to the patient. A firsthorizontal branch 132 of groove 121 a intersects vertical branch 129 ata junction 135 a and extends to a lateral side surface 131 of tubingholder portion 123. A second horizontal branch 134 of groove 121 aintersects vertical branch 129 at a second junction 135 b and alsoextends to the lateral side surface 131 of the tubing holder portion123. In the illustrated embodiment, fluid path 126 may be routed fromtop surface 130 to side surface 121 a of tubing holder portion 123 andaway from the patient by inserting tubing 124 into a top portion ofvertical branch 129, junction 135 a, and first horizontal branch 132. Ofcourse, other configurations are possible. For example, in oneembodiment, tubing 124 may be inserted into top and middle portions ofvertical branch 129, junction 135 b, and second horizontal branch 134,which would allow for an adjustment of the distance between top surface120 and orifice 128 of tubing 124, i.e., how far tubing 134 is insertedinto the patient's nostril.

The illustrated embodiment provides a symmetrical design relative to acentral, substantially horizontal axis when body portion 122 is mountedto the patient and the patient's head is in a normal, upright positionrelative to horizontal. Of course, groove 121 a may have otherconfigurations. In the illustrated embodiment, groove 121 b has asymmetrical configuration relative to a central, substantially verticalaxis when body portion 122 is mounted to the patient and the patient'shead is in a normal, upright position relative to horizontal. Therefore,details of the branches and the junctions of groove 121 b will not bediscussed in greater detail herein, and common reference characters areused with the common features of groove 121 a. The illustratedembodiment is not intended to be limiting in any way.

Tubing 125 may include a T-shaped junction 136 that is configured to bereceived by one of grooves 121 a, 121 b. As illustrated, groove 121 b isconstructed and arranged to secure T-shaped junction 136, as well asportions of tubing 125 that extend from the T-shaped junction 136.T-shaped junction 136 in tubing 125 allows one orifice 137 of the tubingto be positioned to communicate fluid path 127 with the patient'snostril, and another orifice 138 of tubing 125 to be positioned tocommunicate fluid path 127 with the patient's mouth, as shown in FIG.15. Tubing 125 may typically be used for carbon dioxide sampling, butmay also be used for oxygen delivery purposes.

It should be appreciated that the embodiment illustrated in FIGS. 15 and16 allows for patient interface 120 to be configured for the specificneeds of the patient. For example, if the patient' left nostril ispartially obstructed, thereby making the right nostril more suitable forreceiving oxygen, tubing 124 may be inserted into groove 121 b andoxygen may be supplied through tubing 124 and orifice 128 to the leftnostril via fluid path 126. In addition, tubing 125 may be inserted ingroove 121 a so that carbon dioxide may be sampled from the patient'spartially obstructed right nostril as well as the mouth. Also, onetubing may be inserted into either groove 121 a, 121 b and the othergroove may be left empty. It is also contemplated that multi-lumentubing may be inserted in either groove 121 a, 121 b so that oxygen maybe delivered and carbon dioxide may be sampled from the same nostril.

Patient interface 120 also includes a mounting structure 139 formounting body portion 122 to the head of the patient. As illustrated,mounting structure 139 includes a pair of straps 140 that extend fromthe body portion on opposite sides thereof and are configured to bereceived by the ears of the patient. Although only one of the straps isfully illustrated, the other strap may have the same configuration. Asshown, strap 140 is connected at one end from side surface 131 of tubingholder portion 123, extends around the patient's ear, and is attached toside surface 131 at the other end. The length of strap 140 is sized sothat body portion 122 is properly positioned between to the patient'snose and mouth, yet is still comfortable to the patient. As such,different sized patient interfaces 120 are envisioned so that a morecustom fit may be provided to the patient. In another embodiment, straps140 may be adjustable in length so that a “one size fits all” patientinterface 120 may be provided.

FIG. 17 illustrates yet another embodiment of a patient interface 150that includes a body portion 152 configured to communicate with at leastone fluid path, such as fluid path 151, as shown. Patient interface 150may be an oral and nasal gas sampling and/or gas delivery cannula orappliance. Body portion 152 includes a section 153 that is inflatable bya fluid so as to provide a pillow-like structure, which may increasepatient comfort when the patient interface is mounted to the patient.Two nostril interfaces 154, 155 extend from the body portion 152 and areconstructed and arranged to communicate at least one nostril of thepatient with fluid path 151.

Inflatable section 153 of body portion 152 may be configured to be incommunication with fluid path 151 such that the inflatable section isinflatable with fluid from the fluid path. In an exemplary embodiment,the fluid in fluid path 151 is oxygen. By supplying the fluid toinflatable section 153 with a sufficient back pressure to keep theinflatable section inflated, a “pillow” that is able to substantiallyconform to the patient's facial anatomy is created.

Inflatable section 153 may be manufactured from an elastomeric material,such as polyurethane, which allows the inflatable section to beflexible, so that it is relatively easy to inflate and conform to thepatient's face, while also providing a substantially soft feel to thepatient. In an embodiment, the entire body portion 152 is manufacturedfrom the elastomeric material. It is also contemplated that in anotherembodiment, inflatable section 153 may be not be configured to be incommunication with fluid path 151 but instead is constructed andarranged to be inflated manually with a pump or syringe and then sealed,either prior to or after patent interface 150 is mounted to the patient.

As shown in FIG. 17 and in greater detail in FIG. 18, in an embodiment,one of nostril interfaces 154 is in fluid communication with the fluidpath 151 via a conduit 156 within body portion 152, and other nostrilinterface 155 is in fluid communication with a second fluid path 157with another conduit 158. Fluid paths 151 and 157 may be provided bysuitable tubing 159 and 160, respectively, that are configured to beconnected to body portion 152 by methods previously discussed. In theembodiment illustrated in FIGS. 17 and 18, the patient interface isarranged to provide oxygen to one of the patient's nostrils and tosample the fluid being exhaled by the patient from the other nostril.

As shown in FIG. 19, in one exemplary embodiment, both nostrilinterfaces 154 and 155 are configured to communicate with fluid path 157via a conduit 161. In this embodiment, the received fluid path 151 mayalso be communicated to each of the nostril interfaces 154, 155 viaanother conduit (not shown) located next to but separate from theconduit 161. In addition, an orifice 162 may be provided in orcommunicated to inflatable section 153 so that fluid path 151communicates with the patient's mouth. It should be appreciated thatdifferent configurations are possible by providing suitable conduitswithin the body portion that communicate with fluid paths 141, 157 andnostril interfaces 154, 155. Also, tubing 160 defining fluid path 157may be contained within inflatable section 153 or may be connected tothe inflatable section. The illustrated embodiments are not intended tobe limiting in any way.

As shown in FIG. 17, patient interface 150 also includes a mountingstructure 163 that includes a pair of straps 164 that are configured toextend from body portion 152 on opposite sides thereof to the ears ofthe patient to hold the body portion in a fixed position relative to thenostrils of the patient. Although only one strap 164 is fullyillustrated, the other strap may have the same configuration. As shown,each strap 164 includes a ring 165 at one end that is configured tosurround the ear around a circumference thereof. The straps arepreferably made from an elastic material, such as rubber, so that theymay be stretched away from body portion 152 and mounted to the patient'sears with sufficient tension so as to hold the body portion in a fixedposition relative to the nose of the patient. Straps 164 should be sizedsuch that sufficient tension, but not too much tension, is provided, astoo much tension may affect the sustainable pressure in inflatablesection 153.

FIG. 20 illustrates an embodiment of a patient interface 170 that can bused an oral and nasal gas sampling and/or gas delivery cannula orappliance. Patient interface 170 includes a body portion 172 configuredto communicate with a fluid path 171. Fluid path 171 may be defined bytubing 173, as shown in FIG. 20. The fluid path may be configured toreceive a fluid being exhaled by the patient through the nasal cavityand/or the oral cavity, or fluid path 171 may be configured to supply afluid containing oxygen to be inhaled by the patient through the nasalcavity and/or oral cavity.

Patient interface 170 also includes two nostril interfaces 174, 175 thatextend from body portion 172, as shown in greater detail in FIG. 21.Each nostril interface 174, 175 is configured to be received by apatient's nostril, and either one or both are in communication withfluid path 171. As discussed above, body portion 172 may includeinternal conduits or passageways that communicate nostril interfaces174, 175 with fluid path 171. In addition, tubing 173 may be connectedto body portion 172 by using similar method and structures discussedabove.

Patient interface 170 also includes an attachment portion 176 thatincludes two extensions 177, 178 that extend from opposite sides of thebody portion 172. Extensions 177, 178 may each include of a wing-likemalleable structure that is conformable to the patient's face. Theextensions, at least in part, provide stability to the patient interface170, when the interface is mounted to the patient. An adhesive 179 isprovided on distal ends 180, 181 of extensions 177, 178. Adhesive 179 isconfigured to removably attach attachment portion 176, via extensions177, 178, to the patient's face so as to hold body portion 172 in afixed position relative to the nose of the patient, so that nostrilinterfaces 174, 175 are held in a fixed position. Adhesive 179 should bea material that is strong enough to temporarily bond attachment portion176 to the patient's face, yet be easily removed.

Body portion 172 may also be configured to receive a second fluid path182, defined by tubing 183. If fluid path 171 is configured to receivethe fluid being exhaled by the patient, second fluid path 182 may beconfigured to supply a fluid containing oxygen to the patient forinhalation.

In the illustrated embodiment, both fluid paths 171, 182 may be receivedby body portion 172 on a same side of the body portion. In anotherembodiment, fluid paths 171, 182 may be received on opposite sides ofbody portion 171 such that tubing 173, 183 extend from body portion 162in substantially opposite directions. It is also contemplated that anoral sampler may be added to the embodiments shown in FIGS. 20 and 21.The oral sampler may be a separate adjustable structure that is securedto body portion 172, or the body portion may be formed so as to allowthe collection of gases being expired from the mouth. The illustratedembodiment is not intended to be limiting in any way.

FIG. 22 illustrates a patient interface 190 that includes a firstnostril interface 191 that is configured to be inserted into a firstnostril of the patient, and a second nostril interface 192 that isconfigured to be inserted into a second nostril of the patient. Firstnostril interface 191 includes a conduit 193 for communicating with thefirst nostril of the patient. Similarly, second nostril interface 192includes a conduit 194 for communicating with the second nostril of thepatient. As discussed in further detail below, first nostril interface191 is capable of relative sliding movement with respect to secondnostril interface 192 to enable an adjustment of the spacing between thenostril interface 191 and second nostril interface 192.

As illustrated, patient interface 190 includes an interconnectingstructure 195. First nostril interface 191 and second nostril interface192 both frictionally engage interconnecting structure 195 such thatsliding frictional movement of the first nostril interface and/or of thesecond nostril interface along the interconnecting structure enables theadjustment of the spacing between the first and the second nostrilinterfaces. In an alternative embodiment, one of the nostril interfaces,such as first nostril interface 191, may be joined with interconnectingstructure 195 by suitable methods, such as bonding, so that the firstnostril interface does not slide relative to interconnecting structure195 and only the second nostril interface is capable of slidingadjustment.

As shown in the embodiment of FIG. 22, interconnecting structure 195takes the form of tubing 196 that communicates a fluid path 197 to thefirst nostril interface 191 via conduit 193. First nostril interface 191includes engagement surfaces 198 that are configured to slidablysealingly engage tubing 196 such that a lower enlarged cavity 200defining a space within the first nostril interface is sealed from thesurrounding environment. This sealing engagement substantially preventsthe fluid being communicated between fluid path 197 and first nostrilinterface 191 from leaking between the first nostril interface at thepoints of contact with tubing 196 forming the interconnecting structure195. Tubing 196 includes at least one orifice 201 at a portion of thetubing that is inside cavity 200, so that the fluid may be communicatedbetween fluid path 197 and first nostril interface 191. Cavity 200 maybe part of conduit 193 or may communicate with conduit 193. Orifice 201may be a single larger orifice or may include a plurality of smallerorifices, as shown in FIG. 22.

Tubing 196 may also be configured to communicate a second fluid path 202to second nostril interface 192. Specifically, second nostril interface192 may be configured to slidingly, frictionally engage tubing 196 suchthat the tubing communicates second path 202 to second nostril interface192 via conduit 194. The second nostril interface includes engagementsurfaces 199 that are configured to sealingly engage tubing 196 suchthat an enlarged cavity 204 defining a lower space within second nostrilinterface 192 may be sealed from the surrounding environment. Thisprevents the fluid being communicated between second fluid path 202 andsecond nostril interface 192 from leaking between the second nostrilinterface at the points of contact with tubing 196 forminginterconnecting structure 195. Tubing 196 includes an orifice 205 at aportion of the tubing that is inside cavity 204, so that the fluid maybe communicated between second fluid path 202 and second nostrilinterface 192. Cavity 204 may be part of the conduit 194 or maycommunicate with the conduit 194. The orifice 205 may be a single largerorifice, as shown in FIG. 22, or may include a plurality of orifices.

Patient interface 190 may also include a movement limiting structure 206that limits movement between first nostril interface 191 and tubing 196,so that the position of orifice 201 is retained within cavity 200. Themovement limiting structure 206 may also be configured to limit movementbetween second nostril interface 192 and tubing 196, so that theposition of orifice 205 is retained within cavity 204. In oneembodiment, movement limiting structure 206 may include a web ofmaterial 207 that interconnects first nostril interface 191 with secondnostril interface 192. Web of material 207 may be a cloth or may be aflexible plastic, for example.

In another embodiment, movement limiting structure 206 includes a stopstructure that is formed on tubing 196. The stop structure may includeportions 208 a and 208 b that are configured to abut against outsidesurfaces 209 a and 209 b of first nostril interface 191 such thatportions 280 a and 208 b may not pass into cavity 200. Similarly, thestop structure may also include portions 208 c and 208 d that areconfigured to abut against outer surfaces 210 a and 210 b of secondnostril interface 192 such that portions 208 c and 208 d may not passinto cavity 204.

As shown in FIG. 22, patient interface 190 may also include an oralsampler 211 that may be received by one of nostril interfaces 191, 192.Oral sampler 211 has an orifice 212 located proximate to the patient'smouth when patient interface 190 is mounted to the patient. Oral sampler211 includes a conduit 213 for communicating a fluid between thepatient's mouth and the second fluid path 202. In the illustratedembodiment, oral sampler 211 is received by second nostril interface 192in a frictional engagement. It is also contemplated that oral sampler211 may be permanently connected to nostril interface 192 with asuitable adhesive or plastic weld.

In another embodiment, interconnecting structure 195 may be a structureother than the tubing. For example, the interconnecting structure maycomprise a direct link between nostril interfaces 191, 192. Morespecifically, nostril interface 191 may have a projection received in atightly toleranced receptacle formed on the outer surface of nostrilinterface 192, to permit a sliding friction fit therebetween. In thisarrangement of a connecting structure, nostril interfaces 191, 192 maybe directly welded or otherwise bonded to respective tubing ends of theassociated fluid paths, so that no movement of nostril interfaces 191,192 occurs with respect to the associated tubing in fluid communicationtherewith.

The illustrated embodiment is not intended to be limiting in any way. Inan embodiment, nostril interface 191, 192 and web of material 207 may beassembled first, and oral sampler 211 may be added at the end of themanufacturing process, or may not be added at all. Instead, a sealingstructure (not shown) may be used to seal nostril interface 192 if thepatient interface is not intended to be used for oral sampling ordelivery. Because oral sampler 211 can be added at the end ofmanufacture, the oral sampler can be selected from a plurality ofprefabricated sampler sizes and shapes, based on the size of the patientand spacing between the nose and mouth, as well as the shape of themouth and expiratory flow pattern (e.g. pulsed breathing versus normalbreathing).

For embodiments in which patient interface 190 is to be used as asampling and delivery cannula, two fluid paths 197, 202 may be separatedwith a separator 214 within the tubing 196. For embodiments in whichpatient interface 190 is to be used as a sampling-only cannula, fluidpaths 197, 202 may be communicated within tubing 196, or alternatively,the tubing may form a single fluid path that receives expired fluid fromboth nostril interfaces 191, 192.

To mount patient interface 190 to the patient, tubing 196 may beconfigured to extend from first nostril interface 191 and second nostrilinterface 192 and at least partially around each of the patient's earsin a similar manner that is illustrated in the embodiment shown in FIG.1, for example. Of course, any suitable structure may be used to mountpatient interface 190, or any of the patient interfaces disclosedherein, to the patient.

FIG. 23 illustrates an embodiment of a patient interface 220 thatincludes an integrally formed structure 221. Integrally formed structure221 includes a tubing portion 222 and an appliance portion 223.Integrally formed (e.g. extruded) plastic tubing portion 222 defines afirst fluid path 224, and a second fluid path 225. The appliance portion223 includes a first nostril interface 226, which communicates withfirst fluid path 224, and a second nostril interface 227, whichcommunicates with second fluid path 225.

As shown in FIG. 24, tubing portion 222 includes a separator 228 (e.g.wall) for separating first fluid path 224 from second fluid path 225.This allows tubing portion 222 to be configured to receive a fluid beingexhaled from the patient as well as supply a fluid, such as oxygen, tobe inhaled by the patient. Fluid paths 224, 225 may be of an equalcross-section, or one of the cross-sectional areas may be larger thanthe other. For example, in an embodiment, the cross-sectional area offluid path 225 that supplies oxygen to the patient is larger than thecross-sectional area of fluid path 224 that receives fluid from thepatient to minimize the pressure drop of tubing portion 222. Theillustrated embodiment is not intended to be limiting in any way.

As shown in FIG. 25, appliance portion 223 also includes a separator 229that defines a first conduit 230 that extends between first nostrilinterface 226 and first fluid path 224 and a second conduit 231 thatextends between second nostril interface 227 and second fluid path 225.As such, separator 229 separates fluid communication between firstnostril interface 226 and second nostril interface 227.

Tubing portion 222 and appliance portion 223 are connected, for example,in an ultrasonic welding or heat fusion process, such that separator 228in the tubing portion and separator 229 in the appliance portion areconnected, thereby separating fluid communication between first fluidpath 224 and second fluid path 225 throughout integrally formedstructure 221. First fluid path 224 may communicate fluid from the nasalcavity of the patient that is exhaled through one of the patient'snostrils, and second fluid path 225 may communicate another fluid, suchas oxygen, to the nasal cavity of the patient through the other nostril.Appliance portion 223 may also include an oral sampler. The illustratedembodiment is not intended to be limiting in any way.

As shown in FIG. 26, each of nostril interfaces 226, 227 may include aplurality of ribs 230 that extend from an outer surface 231 of thenostril interface 226, 227 at a distal end 232 thereof. Ribs 230 areconfigured to position each nostril interface 226, 227 so that anorifice 233 at distal end 232 of each nostril interface 226, 227 may belocated away from the inside surface of the respective nostril. Inaddition, ribs 230 may help reduce the intake of liquids and solids fromthe nasal cavity. This may allow for a less obstructed flow of fluidbeing supplied to or received from the nasal cavity. This ribbedstructure may be used with any nasal cannula disclosed herein.

To assist with holding tubing portion 221 in place relative to thepatient, patient interface 220 may also include a spring clip 234 thatis configured to removably attach tubing portion 221 to the patient'sear or an article of clothing. In one embodiment, the spring clip may beof a clothespin type construction, with an aperture therethroughadjacent the pivot axis, which aperture is dimensioned to slidably,frictionally receive the tubing portion 221 therethrough.

As shown in FIG. 23, appliance portion 222 may also have a securementportion 235 that is disposed proximate to one of nostril interfaces 226and is constructed and arranged to engage an exterior surface of thepatient's nose such that the securement portion and the nostrilinterface are cooperable, such that the resiliency of the plasticmaterial thereof enable clamping of an alar sidewall portion of thepatient's nose therebetween. In an embodiment, a second securementportion may be disposed proximate to other nostril interface 227 and maybe configured to engage an exterior surface of the patient's nose suchthat the second securement portion and the nostril interface arecooperable to clamp the other alar sidewall portion of the patient'snose. The illustrated embodiment is not intended to be limiting in anyway.

FIG. 27 illustrates another embodiment of a patient interface 250 of thepresent invention configured to be a gas sampling and/or gas deliverycannula that samples and/or delivers fluid from/to a single nostril. Itis contemplated that patient interface 250 may be particularlyadvantageous if a naso-gastric feeding tube is in use, therebyeffectively making one nostril unavailable for sampling or oxygendelivery.

As illustrated, patient interface 250 includes a body portion 252 thatis configured to communicate with a fluid path 251. A single nostrilinterface 253 extends from body portion 252 and is configured to bereceived by the patient's nostril, and to provide fluid communicationbetween the nasal cavity via the nostril and fluid path 251.

In the illustrated embodiment, fluid path 251 is defined by tubing 254.In one embodiment, tubing 254 is configured to carry fluid exhaled bythe patient through the nasal cavity via one nostril to a receiver, suchas a gas analyzer, for determining the concentration of carbon dioxidein the fluid over time. In another embodiment, tubing 254 is configuredto supply a fluid containing oxygen, to the nasal cavity as the patientinhales though the nostril.

It is also contemplated that tubing 254 may be configured to also definea second fluid path, either in the manner discussed above andillustrated in FIG. 24, or in the manner illustrated in FIG. 30, or inthe manner illustrated in FIG. 55, which is discussed in greater detaillater. Similarly, in an embodiment, body portion 252 and nostrilinterface 253 may include separators that separate the fluidscommunicated between the nostril and the first and second fluid paths.An example of a single nostril interface that communicates two fluids inseparate paths is discussed in further detail below and illustrated inFIG. 31.

Interface 250 also includes a securement portion 255 that is disposedproximate to nostril interface 253 and is constructed and arranged toengage an exterior surface of the patient's nose such that thesecurement portion and the nostril interface are cooperable to securelyengage or lightly clamp an alar sidewall portion of the patient's nosetherebetween. The resiliency of the material forming securement portion255 and/or of nostril interface 253 create an inwardly directed springforce once these portions are separated to receive the alar sidewalltherebetween so as to engage or lightly clamp the alar sidewall portionof the patient's nose between the nostril interface and the securementportion.

As illustrated in FIG. 27, patient interface 250 also may optionallyinclude a second securement portion 256 that is disposed more proximateto nostril interface 253 than first securement portion 255. Secondsecurement portion 256 may be constructed and arranged to cooperate withfirst securement portion 255 so as to clamp a portion of the patient'snose therebetween. Such an arrangement would not interfere with nostrilinterface 253, and would not require the nostril interface toparticipate in the clamping function.

As shown in FIG. 27, the patient interface 250 may include a head gearthat includes a strap 257 that is configured to be received by an ear ofthe patient and is also connected to the tubing 254 so as to supporttubing 254. As illustrated, strap 257 includes an opening 258 forreceiving the ear, and a holder 259 that is configured to engage aportion of the tubing 254 and allow the tubing 254 to pass therethroughwithout creating a kink in the tubing. It is also contemplated that insome embodiments, rather than having the strap 257, patient interface250 may include a clip, like clip 234 illustrated in FIG. 23 that isconfigured to be clamped to the ear of the patient so that the ear maysupport tubing 254 more directly. The illustrated embodiment is notintended to be limiting in any way.

FIG. 28 illustrates a patient interface 270 according to a still furtherembodiment of the invention. Patient interface 270 includes a head mount272 that is configured to be secured on the head of a patient. Headmount 272 includes a docking portion 273 that is constructed andarranged to be disposed proximate to the nose of the patient, and anappliance 274 that is configured to be removably attached to the dockingportion. Appliance 274 includes at least one nostril interface, such asnostril interface 275, for communicating a fluid path 276 with thenostril of the patient.

Appliance 274 also includes a body portion 277 and tubing 278 that issecured to the body portion. In one embodiment, a distal end 279 of thetubing defines nostril interface 275. Tubing 278 also defines fluid path276. Body portion 277 includes a network of grooves 280 that isconfigured to receive tubing 278 and secure the tubing to the bodyportion. Grooves 280 may be constructed and arranged like grooves 121 a,121 b described above and illustrated in FIGS. 15 and 16, the discussionof which is hereby incorporated by reference.

As illustrated in FIG. 28, a second tubing 281 having a T-shapedjunction 282 and defining a second fluid path 283 may alternatively, oradditionally, be provided and secured to body portion 277 in a similarmanner that is discussed above in regard to the tubing 125 shown inFIGS. 15 and 16.

Head mount 272 includes a pair of straps 283 that extend from thedocking portion 273 on opposite sides thereof and are configured to bereceived by the ears of the patient. Although only one of the straps isfully illustrated, the other strap may have the same configuration. Asshown, strap 283 is connected at one end from a side surface 284 ofdocking portion 273, extends around the patient's ear, and is attachedto side surface 284 at the other end. The length of strap 283 is sizedso that docking portion 273 is properly positioned between to thepatient's nose and mouth, yet is still comfortable to the patient, sothat when the appliance is attached to docking portion 273, the nostrilinterface is properly located relative to the nostril of the patient soas to communicate the fluid paths 276, 283 to the nostrils of thepatient. Of course, the present invention contemplates that anadjustment mechanism can be provided to change the length of strap 283.

A plurality of head mounts having different lengths of straps, but alsohaving docking portions of the same size, may be provided so that headmounts of different sizes may be used with the same appliance. This mayallow the clinician to select a head mount of an appropriate size forthe patient, and attach the appliance to the docking portion of thatparticular head mount. After the appliance has been used, the appliancemay be removed from the docking portion and discarded, and the headmount may be cleaned and/or sterilized and reused on another patient, ifdesired, or the head mount may also be discarded or recycled.

FIG. 29 illustrates a patient interface 310 according to an embodimentof the invention suitable for use as a gas sampling and deliverycannula. Patient interface 310 includes a body portion 312 and a nostrilinterface 313 that extends from the body portion. Nostril interface 313is configured to be received by a nostril of the patient's nose. Patientinterface 310 also includes tubing 314 that is connected to body portion313. Tubing 314 defines a first fluid path 315 and a second fluid path316.

As shown in FIG. 30, in an exemplary embodiment, tubing 314 includes aseparator 317 that separates first fluid path 315 from second fluid path316 such that the second fluid path substantially surrounds orcompletely surrounds the first fluid path. Alternatively, two separatetubes may be connected to opposite sides of body portion 312, one tubefor delivering oxygen, the other drawing samples of expired gas.

As shown in the embodiment of FIG. 31, body portion 312 has a firstpassage 318 therein that is configured to communicate with first fluidpath 315 configured to withdraw a fluid from the nasal cavity of thepatient. Body portion 312 also has a second passage 319 configured tocommunicate with second fluid path 316 to supply a fluid, such asoxygen, to the patient so that the patient may inhale the second fluid.

A shown in greater detail in FIG. 32, nostril interface 313 has a firstorifice 320 at a distal end 321 thereof that is configured tocommunicate with first passage 318 of the portion 312 and is alsoconfigured to receive the fluid from the patient. Nostril interface 313also includes a second orifice 322 at an outside circumferential surface323 thereof that is configured to communicate with the second passage319 of body portion 312 and is also configured to output fluid (oxygen)to the patient. In the illustrated embodiment, second orifice 322includes a plurality of orifices that may allow for an improveddistribution of the fluid being supplied to the patient. The size,shape, and number of orifices 322 can be varied.

As illustrated in FIG. 29, patient interface 310 may also include a headmount 324 that is configured to support tubing 314. Head mount 324 mayinclude a strap 325 that is connected to body portion 312 and extendsfrom the body portion to the patient's ear. Although only one strap isillustrated, head mount 324 may include a second strap that isessentially the same as strap 325. As such, only strap 325 will bediscussed herein.

Strap 325 includes a ring portion 326 on one end thereof that isconfigured to circumferentially surround the patient's ear, as shown inFIG. 29. Strap 325 also includes a holder portion 327 between the ringportion 326 and the body portion 312. Holder portion 327 is configuredto hold a portion of tubing 314 in a manner that does not create a kinkin the tubing and also allow the tubing to extend therethrough. The headmount is configured to hold body portion 312 in a fixed position betweenthe patient's nose and mouth. The other strap (not illustrated) may beconfigured to be connected to body portion 312 at one end and may alsohave a ring portion at the other end to circumferentially surround thepatient's other ear.

In addition, as shown in FIG. 29, other tubing 328 may be connected tobody portion 312 to function as a further support for the body portionso that the body portion 312 and nostril interface 313 stay in a fixedposition. In such an embodiment, the other strap may also support tubing328 with a holder portion in a similar manner as holder portion 327 thatis illustrated.

It is also contemplated that body portion 312 may be configured so thatonly one of fluid paths 315 is defined by tubing 314 and second fluidpath 316 is defined by tubing 328. Body portion 312 may include internalconduits or passageways that communicate the fluid being received fromthe patient from first orifice 320 in nostril interface 313 to firstfluid path 315, and also communicate the fluid being supplied to thepatient from second fluid path 316 to second orifice 322. Theillustrated embodiment is not intended to be limiting in any way.

It is also contemplated that in some embodiments, rather than the havingstraps, head mount 324 may include a clip that is configured to beattached to the patient's ear in a manner that supports tubing 314, likeclip 234 illustrated in FIGS. 23 and described above. The term “headmount” is intended to generally define a structure that allows tubing314 to be supports by the patient's head. The illustrated embodiment isnot intended to be limiting in any way.

In yet another embodiment, the nose clamping arrangement illustrated anddiscussed with respect to the embodiment of FIG. 27 may be employed.

FIG. 33 illustrates an embodiment of a nostril interface 340 that is aslightly modified version of nostril interface 313 described above andillustrated in FIG. 32. Nostril interface 340 is configured to beinserted into a nostril of the patient and includes an inner conduit 342that extends through the nostril interface. Inner conduit 342 isconfigured to receive a fluid that is being exhaled by the patient fromthe nasal cavity via the nostril. Inner conduit 342 includes an orifice343 and a distal end 344 thereof. A proximal end 345 of inner conduit342 is configured to communicate with a fluid path of a patientinterface, cannula, or appliance that communicates the fluid with asupplier or receiver as discussed above.

Nostril interface 340 also includes an outer conduit 346 that surroundsat least a portion of inner conduit 342, as shown in FIG. 33. Outerconduit 346 is configured to communicate a second fluid to the nostrilof the patient so that the patient may inhale the second fluid. Aproximal end 347 of outer conduit 346 is configured to communicate withsecond fluid path of the patient interface, cannula, or appliance thatcommunicates the second fluid with the supplier or receiver.

One of the traditional problems with oxygen delivery to patients is thatthe oxygen is often delivered as a dry gas, which has a tendency to drythe nasal passages. As shown in FIG. 33, nostril interface 340 alsoincludes a moisture exchanger 348 that forms outlet port openings ororifices 350 of outer conduit 346 and surrounds inner conduit 342.

Moisture exchanger 348 is configured to receive moisture from the fluidbeing exhaled by the patient through the nostril (and not enteringorifice 343 of the inner conduit) and to supply at least a portion ofthe moisture contained thereby to the fluid that is being supplied tothe patient through orifice 350. As shown in FIG. 33, moisture exchanger348 is made from a hydrophyllic filter material 352. Such an exchangermay also be a heat-moisture exchanger (HME) that also exchanges heat. Asthe exhaled air passes over moisture exchanger 348, a portion of thewater vapor in the saturated expiratory fluid is absorbed. During thefollowing inspiration, the fluid, such as oxygen, that is delivered tonostril interface 340 passes through moisture exchanger 348 and thewater content of the delivered fluid may be increased from “dry.” Thismay be particularly suited for pulsed oxygen delivery systems. Otherarrangements of the moisture exchanger may be used with the nostrilinterface. The illustrated embodiment is not intended to be limiting inany way.

FIG. 34 illustrates a patient interface 370 according to anotherembodiment of the invention. Patient interface 370 includes a bodyportion 372 that is configured to communicate with a fluid path 374. Thefluid path 374 may be defined by tubing 376, and may be configured tosupply a fluid to the body portion 372. Patient interface 370 alsoincludes a first nostril interface 378 and a second nostril interface379 that extend from body portion 372. First nostril interface 378 isconfigured to be received by one nostril of the patient and secondnostril interface 379 is configured to be received by the other nostril.Body portion 372 includes at least one internal conduit or passagewaythat is configured to communicate fluid path 374 to one or both of thenostril interfaces 378, 379 so that a gas may be supplied to or sampledfrom one or both of nostril interfaces 378, 379, accordingly. In theillustrated embodiment, body portion 372 includes a conduit 380 that isconfigured to communicate fluid path 374 with first nostril interface378. The illustrated embodiment is not intended to be limiting in anyway.

As shown in FIG. 34, patient interface 370 also includes an oral samplerportion 382 that extends from body portion 372. Oral sampler portion 382is configured to receive a fluid being exhaled from the patient's mouth,and communicate the fluid to a second fluid path 386. Second fluid path386 may be defined by tubing 388 that is connected to and extends fromthe sampler portion 382 to a receiver. As discussed above, the receivermay include a gas analyzer so that the concentration of carbon dioxidein the fluid may be determined over time. Body portion 372 may beconfigured to communicate one or both of nostril interfaces 378, 379 tosecond fluid path 386 via internal conduits so that fluid being exhaledby the patient through the nose may also be communicated to thereceiver. In the illustrated embodiment, body portion 372 includes asecond conduit 390 that communicates second nostril interface 379 tofluid path 386. The illustrated embodiment is not intended to belimiting in any way.

Oral sampler portion 382 may include a malleable structure 392 thatallows an orifice 393 at a distal end 394 of oral sampler portion 383 tobe adjusted relative to the patient's mouth. The malleable structure 392may include bellows 395 or an accordion-like structure, as shown, thatallows the oral sampler portion 382 to lengthen, shorten, or berepositioned so that orifice 393 may be optimally positioned. In otherembodiments, the malleable structure include a malleable wire or wires,as described in embodiments above. The illustrated embodiment is notintended to be limiting in any way.

A pair of straps 396 (only one of which is shown in FIG. 34) may extendfrom body portion 372 on opposite sides thereof. Each strap 396 may beconfigured to at least partially surround an ear of the patient to holdthe body portion in a fixed position relative to the nostrils of thepatient. In the illustrated embodiment, tubing 376 is configured to passthrough a distal end 397 of strap 396. The distal end of strap 396 isconfigured to slide along tubing 376 so as to adjust tension in strap396 as well as the tubing when patient interface 370 is mounted to thepatient. Similarly, tubing 388 that extends from oral sampler portion382 may be configured to pass through a distal end of the other strap.The distal end of the other strap may also be configured to slide alongtubing 388 so as to adjust tension in that strap and tubing 388 when thepatient interface is mounted to the patient. Of course, any type of headmount, including the head mounts discussed herein, may be used tosupport the patient interface. The illustrated embodiment is notintended to be limiting in any way.

In embodiments described above, it should be appreciated that theportions of the tubing proximate to the patient may not only act as partof the patient interface (e.g., where the tubing wraps around thepatient's ear), but may also be considered to be part of the appliance.In addition, in some embodiments, the tubing itself acts as the nostrilinterfaces, such as illustrated in FIGS. 15, 16, and 28, for example.

It is contemplated that any of the embodiments of the patient interfacesdescribed herein may include scented portions, or may provide a scentedfluid to the patient to help relieve any anxiety that the patient may beexperiencing. Such an addition of a scent via a nasal cannula has beentried, as evidenced by the article: Redd, W. H., Manne, S. L., Peters,B., Jacobsen, P. B., and Schmidt, H., “Fragrance administration toreduce anxiety during MR imaging,” 1994 J Magn Reson Imaging 4; 4:623-6,which is incorporated herein by reference in its entirety. Scents mayinclude, but are not limited to vanilla or strawberry.

It is also contemplated that features shown and described herein may beused in combinations not specifically described. As such, none of theillustrated and/or described embodiments are intended to be limiting inany way.

A recent study found that patients having significant obstruction intheir nasal passageway could reliably determine which side of the noseis more obstructed. Clarke J D, Hopkins M L, Eccles R., “How good arepatients at determining which side of the nose is more obstructed?” Am JRhinol. 2006 January-February;20(1):20-4, hereby incorporated byreference in its entirety. Accordingly, it may be desirable in someinstances to provide a patient interface that permits gas sampling fromboth nostrils and oxygen delivery preferentially to either the right orleft nostril and that also allows for simple and repeated (as needed)adjustment by either the clinician or patient without removal from theface.

FIGS. 35-40 illustrate a patient interface 400 according to embodimentsof the present invention. Patient interface 400 includes a nasalinterface 402, as shown in FIG. 35, that is configured to be insertedinto the nostrils of the patient for receiving a fluid exhaled by thepatient from the nasal cavity through the nostrils. Specifically, nasalinterface 402 includes a first nostril interface 405 having a firstorifice 403 for communicating with the first nostril, and a secondnostril interface 406 having a second orifice 404 for communicating withthe second nostril. Nostril interfaces 405, 406 that are to be receivedby the nostrils may be curved so as to substantially conform to thecurvature in the nostrils. Each nostril interface 405, 406 includes asealing portion 407, 408, respectively, that is positioned to remainoutside of the nostrils, as will be discussed in further detail below.

Patient interface 400 also includes a fluid delivery conduit 410, asshown in FIG. 36, that is configured to deliver a fluid to at least oneof the nostrils of the patient. As discussed in further detail below,fluid delivery conduit 410 is movable relative to nasal interface 402.Fluid delivery conduit 410 includes at least one output orifice 412. Inthe embodiment illustrated in FIGS. 37, 39, and 40, fluid deliveryconduit 410 includes two output orifices 413, 414, each of whichsubstantially surrounds a corresponding nostril interface 405, 406 ofnasal interface 402. As shown in FIG. 37, once the nostril interface isinserted into fluid delivery conduit 410, nostril interfaces 405, 406extend through output orifices 413, 414, and sealing portions 407, 408remain inside of fluid delivery conduit 410 in a sealing relationshipwith respect to output orifices 413, 414.

Fluid delivery conduit 410 may be a pillow-like structure that is madeof soft, conformable material such as polyurethane so as to function asan inflatable nasal pillow, much like the structure discussed above andillustrated in FIG. 17, when the fluid is communicated to fluid deliveryconduit 410 from tubing 416 that defines a fluid path 417.

As shown in FIG. 37, a connecting portion 420 of nasal interface 402extends through an end 419 of fluid delivery conduit 410 that isopposite end 418 that receives fluid path 417. Connecting portion 420 isconfigured to connect with a fluid path that communicates the fluidbeing exhaled by the patient through the nostrils for delivery to a gasanalyzer.

End 419 may initially be closed off by a flexible membrane 421. Flexiblemembrane 421 may be punctured by the harder material of connectingportion 420. Subsequently, resilient engagement between flexiblemembrane 421 and connecting portion 420 provides a sliding sealedengagement to inhibit leakage of oxygen during sliding movement ofdelivery conduit 410 relative to nasal interface 402. Alternatively,after puncturing, flexible membrane 421 may be bonded to connectingportion 420 such that the flexible member moves (flexes) with nasalinterface 402 when the fluid delivery conduit and the nostril interfacemove relative to each other. Connecting portion 420 is configured to beconnected to tubing 422 that defines a fluid path 424 for receivingexpired gas.

In an embodiment, patient interface 400 may be configured to be usedsolely as a gas delivery cannula. As shown in FIG. 38, end 420 of nasalinterface 402 may be connected to tubing 416 at end 418 of fluiddelivery conduit 410 in a similar manner described above with regard tothe connection of end 420 and tubing 422. In such an embodiment, end 419may be sealed off completely by flexible membrane 421.

The delivery of oxygen to at least one nostril of the patient may becontrolled by the position of fluid delivery conduit 410 relative tonasal interface 402. For example, when fluid delivery conduit 410 is ina first position relative to the nasal interface 402, as shown in FIG.37, fluid delivery conduit 410 is configured to deliver oxygen to bothnostrils of the patient. In the first position, nostril interfaces 405,406 of the nasal interface 402 are located substantially in the middleof outlet orifices 413, 414, thereby allowing oxygen to flow aroundsealing portions 407, 408 and into the nostrils of the patient.

As shown in FIG. 39, when fluid delivery conduit 410 is in a secondposition relative to the nasal interface 402, fluid delivery conduit 410is configured to deliver the oxygen mostly, or even completely, to onlyone of the nostrils of the patient. This is due to the positions ofsealing portions 407, 408 relative to outlet orifices 413, 414.Specifically, sealing portions 407, 408 do not extend laterally fromnostril interfaces 405, 406 to the same distance on both sides ofnostril interfaces 405, 406. As shown in FIG. 35, inner sections 407 i,408 i of sealing portions 407, 408, respectively, are shorter than outersections 407 o, 408 o of sealing portions 407, 408. Inner sections 407i, 408 i being defined as the sections that are adjacent each other.

Returning to FIG. 39, because inner section 408 i is shorter than outersection 407 o, when fluid delivery conduit 410 is moved slightly to theleft relative to nasal interface 402, the fluid may flow around sealingportion 408, and the fluid generally does not flow around sealingportion 407. In an embodiment, sealing portion 407 may not provide acomplete seal with fluid delivery conduit 410, but may instead provide aslightly leaking seal. Even with a leaking seal, the majority of theflow is only provided to one of the nostrils. As such, the fluid isprovided generally to only one nostril.

Similarly, as shown in FIG. 40, when fluid delivery conduit 410 is movedslightly to the right relative to nasal interface 402, the fluid canflow around sealing portion 407, and the fluid does not flow aroundsealing portion 408. In an embodiment, sealing portion 408 may notprovide a complete seal with fluid delivery conduit 410, but may insteadprovide a leaking seal. Even with a leaking seal, the majority of theflow is only provided to one of the nostrils. As such, the fluid isprovided generally to only one nostril.

By providing an adjustable patient interface so that delivery of afluid, such as oxygen, may be adjusted to one or both nostrils, thefluid may be delivered to the patient more effectively. For example, ifone of the nostrils of the patient is obstructed so that the fluid maynot flow to the nasal cavity, the patient interface 400 may be adjustedso that the fluid is generally provided to the unobstructed nostril.

In addition, where fluid (oxygen) is provided to both nostrils, it ispossible to regulate (adjust) the relative amount of fluid beingprovided to one nostril relative to the other by having one of theopenings left intentionally larger that the other based on the slightlyoff centered position of delivery conduit 410 relative to nasalinterface 402.

Patient interface 400 may be mounted to the patient by any suitablemethod, such as by routing tubing 416, 421 at least partially around theears of the patient, or by connecting the tubing to straps that arereceived by the ear. In an embodiment, either tubing may be replaced by“dummy” tubing that serves as only as a way to mount the interface tothe patient. The embodiments described above are not intended to belimiting in any way.

The patient interfaces described in each of the embodiments above may beconfigured to provide physiological function measurements from centralvascular sites located in and near the nose, e.g. in the outer nosetissues, septum, upper lip, cheeks, etc. Such physiological functionmeasurements may include central photoplethysmography, which may bedefined as the measurement and recording of the photoplethysmogram (PPG)from central vascular sites. Measurements from central sites on apatient's head provide access to well perfused regions, which arebranches of the internal or external carotid arteries.

Central photoplethysmographic measurements offer generally significantlystronger, robust and reliable signals than peripheral sites (sites atthe finger tips or toes). For example, nasal sites may require lesspower, in the order of 10× or more, than peripheral sites, such as thepatient's finger tips, etc. As such, having the ability to combinephysiological function measurements with fluid measurements in the samegeneral location may be clinically valuable. A photoplethysmographicsensor may be used to take such physiological measurements.

Specifically, photoplethysmographic sensors may also be used to measureblood oxygen levels (SPO₂) and effort. Photoplethysmographic sensors maybe transmittance-type sensors, or may be reflectance-type sensors. Atransmittance-type sensor measures light extinction as light passesthrough a portion of blood-perfused tissue. For example, light may betransmitted from one side of a portion of blood-perfused tissue with anemitter, and may be recorded by a detector that is situated across thatportion of the tissue. A reflectance-type sensor measures light that isreflected back from the tissue and includes a transmitter (e.g. a lightsource) and a detector that are locate on the same side of the tissue.For both types of sensors, multiple signals from the detector may beused to estimate the oxygen saturation of the blood and the pulse rateof the patient from changes in absorption of the light detectedthroughout blood pulse cycles. The technology is based on thedifferential absorbance of different wavelengths of light by differentspecies of hemoglobin as explained in further detail in U.S. Pat. No.7,024,235, which is hereby incorporated by reference herein in itsentirety.

Embodiments of the present invention, described in more detail below,relate to the improved patient interfaces, described above, that provideimproved nasal and/or oral carbon dioxide sampling and carbon dioxidesampling and oxygen delivery, and also provide an integratedphysiological function sensor, such as a central photoplethysmographicsensor.

FIG. 41 illustrates a patient interface 440 according to an embodimentof the invention. As illustrated, the patient interface 440 includes thefeatures and attributes of the patient interface 10 illustrated in FIGS.1-3. Accordingly, common features are labeled in FIG. 41 with the samereference characters that are shown in FIGS. 1-3, and will not bedescribed in detail here. The interface 440 of the present embodimentmay be an oral and nasal carbon dioxide sampling cannula or appliance,with optional oxygen delivery, that also includes a physiologicalfunction sensor 442 that is connected with the body portion 12, as shownin FIG. 41. In an embodiment, sensor 442 is a photoplethysmographicsensor.

In the embodiment illustrated in FIG. 42, sensor 442 includes an emitter444 and a detector 446. Emitter 444 of the sensor 442 is configured toengage an outside surface of an alar sidewall of the nose, and detector446 of sensor 442 is configured to engage an inside surface of the alarsidewall of the nose so that the alar sidewall is located in betweenemitter 444 and detector 446. It is also contemplated that the emittermay engage an inside surface of the alar sidewall and the detector mayengage an outside surface of the alar sidewall. In an embodiment,emitter 444 and detector 446 are respectively formed on opposite legs443 and 445, respectively, of a U-shaped resilient structure forming apart of the body of sensor 442, so that when legs 443, 445 of theU-shaped configuration are separated to receive the alar sidewall, theresiliency of sensor 442 allows it to clip or clamp the alar sidewallbetween legs 443, 445. Such clamping may improve the signal that isgenerated by the sensor because outside effects may be reduced.

In an embodiment, emitter 444 includes a light source 448, which may bea red or infrared LED or light emitting diode. In another embodiment,emitter 444 also includes second light source 450, which may be aninfrared or red LED. The output of the red LED may be centered at 660 nmand the infrared LED may be centered at 880 nm. However, otherwavelengths of visible and infrared light are also contemplated.Detector 446 is configured to detect the wavelength(s) of light beingemitted by emitter 444 after the light has been transmitted through thetissue in between emitter 444 and detector 446. This type of sensor andthe processing of the signals generated by this type of sensor are knownin the art, and is described in, for example, U.S. Pat. No. 7,024,235,which is hereby incorporated by reference in its entirety.

In an exemplary embodiment, sensor 442 includes an emitter 452 and adetector 454 that may both engage the outside surface of the patient'snose, as shown in FIG. 41. Emitter 452 may include at least one lightsource 456, such as an LED. In such an embodiment, detector 454 isconfigured to detect the light that is reflected from the tissue towhich the emitter emits the light. This type of reflectance type sensoris known in the art, and is described in, for example, U.S. Pat. No.7,024,235, which is hereby incorporated by reference in its entirety,and U.S. Pat. No. 6,263,223, which is hereby incorporated by referencein its entirety.

In another exemplary embodiment, shown in FIG. 43, sensor 442 includesan emitter 458 that engages one side of the septum of the patient'snose, and a detector 460 that engages the other side of the septum sothat the septum is essentially clamped in between the emitter and thedetector. It should be noted that the pressure applied to the septum issufficient so that the sensor stay in place but does not apply unduepressure on the septal region. Similar to the emitters discussed above,emitter 458 may include at least one light source 462, and detector 460may be configured to detect the amount of light that transmits throughthe septum.

A signal may be provided from each detector 446, 454, 460 andcommunicated to a central processor that is configured to process thesignal into meaningful data for the clinician to monitor. For example,from the signal may be used to create a PPG signal and/or determineoxygen saturation (i.e., oxygenation of the blood) in the blood-perfusedtissue from which the signal was created and/or determine therespiratory rate of the patient. As discussed in further detail below,patient interface 440 may also be used as part of an apnea monitor.

Sensor 442 may include a wireless transmitter that sends the signalwirelessly to the central processor. In another embodiment, the sensormay be hardwired, with wiring being harnessed with or integrally formedwith the tubing forming the fluid paths.

Sensor 442 may be used in conjunction with any of the interfacesdiscussed above and illustrated in FIGS. 1-34. The illustratedembodiment is not intended to be limiting in any way.

FIG. 44 illustrates a patient interface 470 according to an embodimentof the invention. Patient interface 470 incorporates the features andattributes of the patient interface 60 illustrated in FIGS. 9-11 anddescribed above. Accordingly, common features are labeled in FIG. 44with the same reference characters that are shown in FIGS. 9-11, andwill not be described in detail here. Interface 470 may be an oral andnasal carbon dioxide sampling cannula or appliance with optional oxygendelivery that also includes a physiological function sensor 472 that isconnected with body portion 62, as shown in FIG. 44. In an embodiment,sensor 472 is a photoplethysmographic sensor.

In the embodiment illustrated in FIG. 44, sensor 472 includes an emitter474 and a detector 476. Emitter 474 of sensor 472 is configured toengage an outside surface of the patient's upper lip (or portion of skinimmediately above the lip), and detector 476 of sensor 472 is configuredto engage an inside surface of the upper lip (or portion of fleshimmediately above the lip) so that a portion of the upper lip (or flesh)is located in between the emitter and the detector. It is alsocontemplated that the emitter may engage an inside surface of thepatient's upper lip and the detector may engage an outside surface ofthe upper lip. In an embodiment, emitter 474 and detector 476 areprovided on a U-shaped clip or clamping arrangement as discussedpreviously, so as to clamp the portion of the upper lip therebetween.Such clamping or secure engagement may improve the signal that isgenerated by the sensor because outside effects may be reduced.

In an embodiment, emitter 474 includes a light source 478, which may bea red or infrared LED or light emitting diode. In another embodiment,emitter 474 also includes second light source 480, which may be aninfrared LED or red LED. Detector 476 is configured to detect thewavelength(s) of light being emitted by emitter 474 after the light hasbeen transmitted through the tissue in between the emitter and thedetector. As discussed above, this type of sensor and the processing ofthe signals generated by this type of sensor are known in the art.

In an exemplary embodiment, sensor 472 includes an emitter 482 and adetector 484 that may both engage the outside surface of the patient'supper lip, as shown in FIG. 45. Emitter 482 may include at least onelight source 486, such as an LED. In such an embodiment, detector 484 isconfigured to detect the light that is reflected from the tissue towhich the emitter emits the light. As discussed above, this type ofreflectance type sensor is known in the art.

Similar to the embodiments described above, a signal may be providedfrom each detector 476, 484 and communicated to a central processor thatis configured to process the signal into meaningful data for theclinician to monitor. As discussed above, the signal may be provided viaa wireless interface or a hardwired interface with the processor. Thesignal may be used to create a PPG signal and/or determine oxygensaturation (i.e., oxygenation of the blood) in the upper lip and/ordetermine the respiratory rate of the patient, as well as othermeasurements from the PPG signal which may be determined via known timeand frequency based methods. Such measurements may include DC level, anddifferent frequency components may be used to determine thoracicpressure and blood pressure, as described in PCT publication no. WO04/080300 A1, which is hereby incorporated by reference in its entirety.The patient interface 470 may also be used as part of an apnea monitor,discussed below.

Sensor 472 may be configured to be used in conjunction with any of theinterfaces discussed above that include an oral sampler. The illustratedembodiment is not intended to be limiting in any way.

FIG. 46 illustrates a patient interface 490 according to an embodimentof the invention. Patient interface 490 includes the features andattributes of patient interface 90 illustrated in FIGS. 13 and 14 anddescribed above. Accordingly, common features are labeled in FIG. 46with the same reference characters that are shown in FIGS. 13 and 14,and will not be described in detail here. Interface 490 may be an oraland nasal carbon dioxide sampling cannula or appliance with optionaloxygen delivery, and a physiological function sensor 492. In anembodiment, the physiological function sensor 492 may be aphotoplethysmographic sensor. Like sensors 442, 472 described above,sensor 492 may be of the transmittance type or a reflectance type.

As shown in FIG. 46, sensor 492 includes an emitter 494 that isconnected to attachment device 94, and a detector 496 that is connectedto one of nostril interfaces 98, 99 that extends into the nostril of thepatient. Emitter 494 engages an outside surface of the nose, anddetector 496 engages in internal surface of the nostril such that aportion of the nose (alar sidewall or above the super-alar crease) islocated in between the emitter and the detector, as shown in FIG. 46. Itis also contemplated that the emitter may engage an internal surface ofthe nostril and the detector may engage an outside surface of the nose.In other words, emitter 494 and detector 496 are located on oppositesides of the same blood-perfused tissue of the nose.

In the illustrated embodiment, emitter 494 includes a light source 498,which may be a red or infrared LED or light emitting diode. In anotherembodiment, emitter 494 also includes second light source 500, which maybe an infrared or red LED. Detector 496 is configured to detect thewavelength(s) of light being emitted by the emitter after the light hasbeen transmitted through the tissue in between the emitter and thedetector. As discussed above, this type of sensor and the processing ofthe signals generated by this type of sensor are known in the art.

In an embodiment, sensor 492 includes an emitter 502 and a detector 504that may both be connected to attachment portion 94 and engage theoutside surface of the patient's nose proximate to each other, as shownin FIG. 47. Emitter 502 may include at least one light source 506, suchas an LED. In such an embodiment, detector 504 is configured to detectthe light that is reflected from the tissue to which the emitter emitsthe light.

Similar to the embodiments described above, a signal may be providedfrom each detector 496, 504 and communicated to a central processor thatis configured to process the signal into meaningful data for theclinician to monitor. As discussed above, the signal may be provided viaa wireless interface or a hardwired interface with the processor. Thesignal may be used to create a PPG and/or determine oxygen saturation(i.e., oxygenation of the blood) in the alar sidewall and/or determinethe respiratory rate of the patient. The patient interface 490 may alsobe used as part of an apnea monitor, discussed below.

FIG. 48 illustrates a patient interface 510 according to an embodimentof the invention. Patient interface 510 includes the features andattributes of the patient interface 170 illustrated in FIG. 21 anddescribed above. Accordingly, common features are labeled in FIG. 48with the same reference characters that are shown in FIG. 21, and willnot be described in detail here. Patient interface 510 may be an oraland nasal carbon dioxide sampling cannula or appliance with optionaloxygen delivery, and a physiological function sensor 512. In anembodiment, physiological function sensor 512 may be aphotoplethysmographic sensor. Like some embodiments of sensors 442, 472,492 described above, sensor 492 may be of the reflectance type.

As shown in FIG. 48, sensor 512 includes an emitter 514 that isconnected to the attachment device 176, specifically to one ofextensions 177, 178, and a detector 516 that is also connected to theattachment device at the same extension as the emitter. Emitter 514 anddetector 516 both engage adjacent portions of the patient's cheek.Emitter 514 may include at least one light source 518, such as an LED.In such an embodiment, detector 516 is configured to detect the lightthat is reflected from the tissue to which the emitter emits the light.As discussed above, this type of reflectance type sensor is known in theart.

Similar to the embodiments described above, a signal may be providedfrom detector 516 and communicated (either wirelessly or hardwired) to acentral processor that is configured to process the signal intomeaningful data for the clinician to monitor. The signal may be used tocreate a PPG and/or determine oxygen saturation (i.e., oxygenation ofthe blood) in the cheek and/or determine the respiratory rate of thepatient. Patient interface 510 may also be used as part of an apneamonitor, discussed below.

FIG. 49 illustrates a patient interface 530 according to an embodimentof the invention. Patient interface 530 includes the features andattributes of patient interface 250 illustrated in FIG. 27 and describedabove. Accordingly, common features are labeled in FIG. 49 with the samereference characters that are shown in FIG. 27, and will not bedescribed in detail here. Patient interface 530 include a carbon dioxidesampling and/or oxygen delivery cannula or appliance that samples and/ordelivers fluid from/to a single nostril and a physiological functionsensor 532. In an embodiment, physiological function sensor 532 may be aphotoplethysmographic sensor.

Similar to the embodiment illustrated in FIG. 41 and discussed above, inthe embodiment shown in FIG. 49, sensor 532 includes an emitter 534 anda detector 536. The emitter is configured to engage an outside surfaceof the nose (the alar sidewall outside surface), and the detector isconfigured to engage an inside surface of the nose (the alar sidewallinner surface) so that a portion of the nose (the alar sidewall) islocated in between the emitter and the detector. It is also contemplatedthat the emitter may be configured to engage an inside surface of thenose and the detector may be configured to engage an outside surface ofthe nose.

In an embodiment, emitter 534 and detector 536 may be biased toward eachother in the manners previously described so as to clamp or securelyengage the portion of the nose (the alar sidewall) therebetween via anattachment structure. For example, emitter 534 may be disposed on afirst securement portion 255, and detector 536 may be disposed on secondsecurement portion 256. Such secure engagement may improve the signalthat is generated by the sensor because outside effects may be reduced.

In an embodiment, emitter 534 includes a light source 538, which may bea red or infrared LED or light emitting diode. In another embodiment,the emitter also includes second light source 540, which may be aninfrared or red LED. The detector is configured to detect thewavelength(s) of light being emitted by the emitter after the light hasbeen transmitted through the tissue in between emitter 534 and detector536. This type of sensor and the processing of the signals generated bythis type of sensor are known in the art, as discussed above.

In an embodiment, shown in FIG. 50, sensor 532 includes an emitter 542and a detector 544 that may both engage the outside surface of thepatient's nose. The emitter may include at least one light source 546,such as an LED. Like the embodiments discussed above, in such anembodiment, the detector is configured to detect the light that isreflected from the tissue to which the emitter emits the light. Thistype of reflectance type sensor is known in the art, as discussed above,and will not be discussed in further detail herein.

Sensor 532 may also be used with embodiments of the patient interfacethat include nostril interface 340 illustrated in FIG. 33. In suchembodiments, detector 536 may be mounted to nostril interface 340 eitheron moisture exchanger 348 or on an outside surface of outer conduit 346,and emitter 534 may be provided on an outside surface of the alarsidewall such that the alar sidewall is located in between the emitterand the detector in a manner described above. Alternatively, a separateU-shaped clip or clamping structure may be used, as described above, sothe sensor does not interfere with the nostril interface.

Similar to the embodiments described above, a signal may be providedfrom detectors 536, 544 and communicated (wirelessly or hardwired) to acentral processor that is configured to process the signal intomeaningful data for the clinician to monitor. The signal may be used tocreate a PPG and/or determine oxygen saturation (i.e., oxygenation ofthe blood) in the upper lip and/or determine the respiratory rate of thepatient. Patient interface 530 may also be used as part of an apneamonitor, discussed below.

It should be appreciated that the physiological function sensorsdescribed above may be adapted to be provided with embodiments of thepatient interface described herein. The illustrated embodiments are notintended to be limiting in any way.

In addition, embodiments of the patient interfaces and physiologicalfunction sensors described above may be used as part of an apnea monitorfor monitoring apnea in a patient. In the United States, an apneamonitor is defined by regulation in 21 C.F.R. § 868.2377(a) as “acomplete system intended to alarm primarily upon the cessation ofbreathing timed from the last detected breath.” As also defined by 21C.F.R. § 868.2377(a), “The apnea monitor also includes indirect methodsof apnea detection, such as monitoring of heart rate and otherphysiological parameters linked to the presence or absence of adequaterespiration.”

A guidance document provided by the U.S. Department of Health and HumanServices entitled “Class II Special Controls Guidance Document: ApneaMonitors; Guidance for Industry and FDA,” issued on Jul. 17, 2002 andhereby incorporated by reference in its entirety, suggests that an apneamonitor should have at least one primary/direct means for detectingapnea; at least one secondary/indirect means for detecting apnea, e.g.,heart rate; a timer to measure the duration of apneic episodes; visualand audible alarms to signal an apneic episode; visual and audiblealarms to signal a secondary/indirect condition due to an apneicepisode; and a sensor fault alarm for both primary/direct andsecondary/indirect means detecting apnea which activates within 5seconds of a sensor failure. Secondary/indirect methods measurephysiologic parameters that change as a result of apnea. For example,apnea may lead to hypoxia, which in turn may lead to bradycardia.Methods for measuring such parameters include pulse oximetry (POX) andelectrocardiography (ECG). A robust, redundant method for apneamonitoring is still sought.

In accordance with an exemplary embodiment of the present invention, anapnea monitor 600 is provided. As shown in FIG. 51, apnea monitor 600includes a primary respiratory detector 602 that is configured todirectly measure patient breathing by monitoring exhalation of a fluidfrom the patient's nasal cavity and/or oral cavity. Primary respiratorydetector 602 may incorporate any of the embodiments of patientinterfaces, cannulas, or appliances described above.

Apnea monitor 600 also includes a secondary respiratory detector 604that is configured to indirectly measure patient breathing by monitoringa physiological function of the patient proximate to the patient's nasalcavity and/or oral cavity. Secondary respiratory detector 604 mayinclude any of the embodiments of physiological function sensorsdescribed above.

As shown in FIG. 51, apnea monitor 600 also includes a processor 606configured to process data from signals output from primary respiratorydetector 602 and secondary respiratory detector 604. Processor 606 isconfigured to use both signals to determine whether an apnea is present,and to signal an alarm or perform some other action if apnea is present.

As shown in FIG. 52, primary respiratory detector 602 may include apatient interface 610 that is configured to be mounted to the patient'shead. Patient interface 610 includes an appliance 612 that includes anostril interface 613 that is configured to receive (and/or supply)fluid from (and/or to) the nasal cavity when the patient breathes.Patient interface 610 also includes a fluid path 614 that iscommunicated with nostril interface 613. Fluid path 614 is configured tocommunicate the fluid to a sensor 620 configured to sense a property ofthe fluid. In an embodiment, patient interface 610 may include an oralsampler 615 that is configured to receive fluid being exhaled from thepatient's mouth. A fluid path 616 is communicated with oral sampler 615and is configured to communicate the fluid to sensor 620.

In an embodiment, sensor 620 may be part of a gas analyzer 622 that isconfigured to analyze a concentration of a gas, such as carbon dioxide,in the fluid over time. Gas analyzer 622 is configured to provide anoutput signal to processor 606.

In an embodiment, sensor 620 is a pressure sensor 624 that is configuredto sense the pressure in the fluid being exhaled by the patient overtime. Specifically, pressure sensor 624 may be in communication withfluid path 616 in a manner that measures the pressure pulses that aregenerated in the fluid path when the patient exhales. If the pressure influid path 616 is not detected to change over a predetermined period oftime, it may be an indication that the patient may have stoppedbreathing. Such pressure sensors are generally known, and will not bedescribed in further detail herein. See, for example, Montserrat J M etal., “Evaluation of Nasal Prongs for Estimating Nasal Flow,” Am J RespirCrit Care Med. 1997 January;155(1):211-5, which is hereby incorporatedby reference in its entirety. Pressure sensor 624 is configured toprovide an output signal to processor 606.

In another exemplary embodiment, sensor 620 is an acoustic sensor 626that is configured to sense whether fluid is being exhaled by thepatient over time. Specifically, acoustic sensor 626 may be located onor near patient interface 610 and positioned such that the signalsgenerated by the sensor when the patient exhales may be measured. Ifsuch signals have not been detected with a predetermined period of time,it may be an indication that the patient may have stopped breathing.Such acoustic sensors are known (and may also be ultrasonic sensors) andwill not be described in further detail herein. Acoustic sensor 626 isconfigured to provide an output signal to processor 606.

In a still further embodiment, sensor 620 is a thermistor 628 that isconfigured to sense the temperature of the fluid being exhaled by thepatient over time. Specifically, thermistor 628 may detect suddenincreases and decreases in the temperature in fluid path 616 thatcorrespond to the normal pattern of breathing by the patient. Suchthermistor sensors are known, and will not be described in furtherdetail herein. See, for example, U.S. Pat. No. 5,190,048, which ishereby incorporated by reference in its entirety. By monitoring suchchanges over time, thermistor 628 may detect when the temperature influid path 616 has not changed for an abnormal period of time, which maybe an indication that the patient has stopped breathing. Thermistor 628is configured to provide an output signal to processor 606.

As indicated above, secondary detector 604 may include a physiologicalfunction sensor 630, of the type discussed above. In such embodiments,the secondary detector may be mounted to appliance 612 and may be acentral photoplethysmographic sensor. At least a portion of secondarydetector 604 may be configured to engage an external surface of aportion of the nose, or the septum of the nose, or the upper lip of thepatient, or the face (e.g., cheek) of the patient in a manner that isdescribed above and illustrated in the figures.

In an embodiment, secondary respiratory detector 604 is configured tosend another output signal to processor 606 from which the respiratoryrate of the patient may be derived independent from primary respiratorydetector 602. The technique of receiving a signal from physiologicalfunction sensor and deriving the respiratory rate of the patient fromsuch sensing is known in the art from, for example, PCT publication no.WO 00/21438, which is hereby incorporated by reference in its entirety,and US patent application publication no. 2005/0027205, which is herebyincorporated by reference in its entirety.

In an embodiment, as shown in FIG. 53, a method for monitoring apnea 700is provided. The method starts at step 702. At step 704, the patient'srespiration is monitored with a primary respiratory detector. Forexample, the patient's inhalation of oxygen or the patient's exhalationof a fluid from the nasal cavity or oral cavity is monitored at step704. At step 706, a physiological function of the patient proximate tothe patient's nasal cavity or oral cavity with a secondary respiratorydetector 604 is monitored. At step 708, data from output signals ofprimary respiratory detector 602 and secondary respiratory detector 604are processed. At step 710, a determination is made as to whether apneais present, based on the processing of the signals at step 706. If it isdetermined that an apnea is present, the method continues to step 712where an alarm is signaled. The method ends at step 714. If it isdetermined that apnea is not present, the method returns to step 704. Ofcourse, the monitoring of the exhalation at step 704 and the monitoringof the physiological function at step 706 may be done simultaneously, orone may be completed just before (e.g., within milliseconds) or justafter (e.g., within milliseconds) the other.

By monitoring the a primary respiratory signal and a secondaryrespiratory signal at the same central site at or near the nose of thepatient, a robust and rapidly responding respiratory rate andmeasurement of a physiological function, such as blood oxygenation, at asingle site may be provided. In addition, by using embodiments of thepatient interface that includes the physiological function sensor, asingle interface may be provided.

This “single site” sensor has numerous potential applications including,for example, conscious sedation, patient-controlled analgesia (PCA),emergency medicine, and ambulatory monitoring. It allows for more robustand reliable monitoring capability by providing data fusion ofrespiratory signals, less sensitivity to low perfusion and motionartifact related problems that may plague peripheral oxygen saturationmeasurements, and a more robust and reliable alarm system. For example,monitoring oxygen saturation using a finger sensor (e.g. peripheralmeasurement) and ventilation via carbon dioxide sampling with aconventional nasal cannula, arguably results in a monitoring system thatis less reliable than that of the present invention because of the knownmotion and low perfusion problems of the peripheral site and thepotential for two separate sites for disconnection.

With a single site sensor, it is expected that the sensitivity andspecificity for detecting clinical events will be greater than with theconventional multi-site approach. This is in part due to greaterrobustness of the central photoplethysmographic signal, as well as thefaster detection of clinical changes by this signal than the peripheralsignal. The morphology of the central photoplethysmogram is lessfiltered by the vasculature than the peripherally measuredphotoplethysmogram and as such provides a much richer signal from whichphysiologic measures may be determined. Patient-controlled analgesia(PCA) allows patients to receive pain medication, such as opioids (e.g.morphine, fentanyl) on-demand. This is typically accomplished byproviding the patient with a button to activate the pump deliverysystem.

To address the growing concerns regarding the safety of PCA,particularly ventilatory depression, capnography measured usingconventional nasal cannula and pulse oximetry usually measured at thefinger has been provided as an option with some conventional PCA pumps.The inclusion of capnography permits the detection of ventilatorydepression occurring as a result of narcotics before decreases inoxygenation in the patients occur. The use of a single site sensor canbe used in conjunction with PCA for safety monitoring and also as inputinto a PCA system for feedback control. This could provide a more robustsystem than can be provided by a conventional sensor configuration.

Conscious sedation, i.e., moderate sedation/analgesia, produced by theintravenously administration of certain medications such as midazolam,propofol and fentanyl, permits a patient to respond to physicalstimulation and verbal commands, and to maintain an unassisted airway.Conscious sedation facilitates diagnostic or therapeutic procedures suchas a biopsy, radiologic imaging study, endoscopic procedures, radiationtherapy, or bone marrow aspiration. Given the associated risks, e.g.,respiratory depression, with conscious sedation, medical organizationshave published guidelines mandating or strongly recommending appropriatemonitoring. This monitoring has included pulse oximetry and capnography.The use of a single site sensor of the present invention can be usedduring conscious sedation for safety monitoring. This provides a morerobust system than can be provided by a conventional sensorconfiguration.

As described for conscious sedation, the features of the single sitesensor can also find application during emergency medicine andambulatory monitoring.

It is also contemplated that the single site sensor of the presentinvention may include reusable and/or disposable components which mayseparable for one another. Embodiments of exemplary gas sampling withreusable components is found in U.S. provisional patent application No.60/833,678, the contents of which are hereby incorporated by referenceherein in their entirety. With single site sensor embodiments includingcomponents such as a photoplethysmographic sensor, it is contemplatedthat this portion may be separable from the rest of the single sitesensor so that it may be cleaned between patients and reused.

It is also contemplated the single site physiological function sensorcable may communicate the measured signals using electrical or pneumaticpathways to measurement components and that these pathways may beseparate physically or integrated as in a multilumen cable comprisingpneumatic and electrical conduits. This pathway may be connected to awearable hub or module that may transmit the data remotely which may bepositioned behind the ear, clipped to belt, or as part of sensor shirt.

Also, a patient interface is contemplated comprising a physiologicalfunction sensor connected with an appliance portion wherein theappliance portion comprises an airway adapter of a sensor for detectinga carbon dioxide gas in an expiratory gas of a subject, comprising anairway case, adapted to be disposed below nostrils of the subject; andan optional mouth guide, adapted to be disposed in front of a mouth ofthe subject so as to define a space in communication with the airwaypassage. Embodiments of airway adapters adapted to be disposed below thenostrils of a subject is found in U.S. patent application Ser. Nos.10/779,852 (US patent publication no. 2004/0206907) and 11/019,792 (USpatent publication no. 2005/0245836), the contents of both which arehereby incorporated by reference herein in their entirety. It iscontemplated that the sensor and airway adapter of the '852 applicationand the '792 application may serve as a primary respiratory detector andthat the physiological function sensor serves as a secondary respiratorydetector.

The embodiments of a single-site sensor shown for monitoring apnea maybe extended to an ambulatory sleep diagnostic sensor. More specifically,the exemplary embodiments of a combined gas sampling andphotoplethysmographic measurement patient interfaces shown in FIGS. 41to 50 may be adapted to be used as a single-site sensor for ambulatorysleep diagnostics. Conventional ambulatory sleep diagnostic systems(such as the Stardust II from Respironics, Inc. Murrysville, Pa.)require that the subject be instrumented with a chest band as asurrogate for effort, a finger sensor for SPO₂ measurements, and a nasalcannula for flow estimation using pressure measurements.

The present invention utilizes a central photoplethysmographic sensor incombination with a flow measurement system. The flow measurement systemmay based upon known methods, such as pressure and/or flow monitoringvia a catheter or via a thermister type of flow monitor. The presentinvention contemplates that the signal from centralphotoplethysmographic sensor, the PPG signal, may be used as anon-invasive surrogate of effort. Examples of such signal are disclosedin U.S. patent applicant Nos. 10/652,992 (US patent publication no.2004/0040560), and 11/758,159, the contents of each of which areincorporated herein by reference.

It is further contemplated that a combined nasal/oral cannulaconfiguration would increase the sensitivity and specificity of thesystem for individuals prone to mouth breathing. EEG electrodes may beadded to the cannula tubing with leads running to an interface. Acousticmicrophones and vibrations sensors may be added anywhere (alreadydiscussed above) along the tubing or cannula to assess snoring and upperairway instability. An accelerometer can be added to determine patientposition relative to gravity and/or provide actigraphy.

FIG. 54 illustrates a further embodiment of a patient interface 260 ofthe present invention configured to be a gas sampling and/or gasdelivery cannula that samples from a single nostril and/or deliversfluid from/to a single nostril or both nostrils. As noted for patientinterface 250, it is also contemplated that patient interface 260 may beparticularly advantageous if a naso-gastric feeding tube is in use,thereby effectively making one nostril unavailable for sampling oroxygen delivery.

As illustrated, patient interface 260 includes a body portion 262 thatis configured to communicate with fluid paths 241 and 243. A singlenostril interface 263 with opening 266 extends from body portion 262 andis configured to be received by the patient's nostril, and to providefluid communication between the nasal cavity via the nostril and fluidpath 243. A fluid delivery portion 267 extends from body portion 262 andincludes a plurality of openings 269 which are in fluid communicationwith fluid path 241. Fluid path 241 and openings 269 are sized to permitdelivery to either/or both of the nares oxygen with a volumetric flow atleast 6 LPM. The present invention contemplates that the length of fluiddelivery portion 267, as well as the number and size of openings 269,could be altered for different sizes of patient interface 260.

In the illustrated embodiment, fluid path 241 is defined by tubing 240.Tubing 24 is configured to carry fluid exhaled by the patient throughthe nasal cavity via one nostril to a receiver, such as a gas analyzer,for determining the concentration of carbon dioxide in the fluid overtime. In another embodiment, tubing 254 is configured to supply a fluidcontaining oxygen, to the nasal cavity as the patient inhales though thenostril.

It is also contemplated that tubing 254 may be configured to also definea second fluid path, either in the manner discussed above andillustrated in FIG. 24, or in the manner illustrated in FIG. 30, or inthe manner illustrated in FIG. 55, which is discussed in greater detaillater. Similarly, in an embodiment, body portion 252 and nostrilinterface 253 may include separators that separate the fluidscommunicated between the nostril and the first and second fluid paths.

Interface 260 also includes a securement portion 265 that is disposedproximate to nostril interface 263 and is constructed and arranged toengage an exterior surface of the patient's nose such that thesecurement portion and the nostril interface are cooperable to securelyengage or lightly clamp an alar sidewall portion of the patient's nosetherebetween. In the embodiment shown, securement portion 265 is curvedand includes a tabbed portion 268 which permits easier gripping andplacement onto the nostril. These features allow easy and comfortableapplication to most subject's nostrils. The resiliency of the materialforming securement portion 265 and/or of nostril interface 263 create aninwardly directed spring force once these portions are separated toreceive the alar sidewall therebetween so as to engage or lightly clampthe alar sidewall portion of the patient's nose between the nostrilinterface and the securement portion.

Patient interface 260 also may optionally include a second securementportion (not shown) that is disposed more proximate to nostril interface263 than first securement portion 265. Second securement portion may beconstructed and arranged to cooperate with first securement portion 265so as to clamp a portion of the patient's nose therebetween. Such anarrangement would not interfere with nostril interface 263, and wouldnot require the nostril interface to participate in the clampingfunction.

Similar to the embodiment illustrated in FIG. 49, securement portion 265may include an emitter portion 261 and a detector portion 264. Theemitter and detector portions are configured to engage an outsidesurface of the nose (the alar sidewall outside surface). The detector isconfigured to detect the wavelength(s) of light being emitted by theemitter after the light has been reflected by the tissue incommunication with emitter portion 261 534 and detector portion 264.This type of sensor and the processing of the signals generated by thistype of sensor are known in the art.

The present invention also contemplates that the emitter portion 261 anddetector portion 264 may be biased toward each other in the mannerspreviously described, so as to clamp or securely engage the portion ofthe nose (the alar sidewall) therebetween. For example, emitter portion261 may be disposed on securement portion 265, and detector 264 may bedisposed on second securement portion (not shown) which engages aninside surface of the nose. Emitter portion 261 includes at least onelight source, which may be a red and infrared LED or light emittingdiode. Also, a plurality of light sources is contemplated. Thisembodiment would allow tissue measurements to be made at differentwavelengths ranging from the ultraviolet to mid-infrared. Applicationsfor such an arrangement include determining the concentration of oxy-and deoxyhemoglobin, as well as dyshemoglobins such as met- andcarboxyhemoglobin. Also determining hemoglobin/hematocrit and othersubstances in the blood/tissue are contemplated. These may be LEDs,semiconductor lasers (e.g. edge emitting, VSCELs) or other light sourcesknown in the art.

As shown in FIG. 55, tubing 240 includes for tubing portions 241 and 243separating first fluid path 242 from second fluid path 243. This allowstubing portion 243 to be configured to receive a fluid being exhaledfrom the patient and tubing portion 241 to supply a fluid, such asoxygen, to be inhaled by the patient. Fluid paths 242, 243 may be of anequal cross-section, or one of the cross-sectional areas may be largerthan the other. For example, in an exemplary embodiment, thecross-sectional area of fluid path 242 that supplies oxygen to thepatient is larger than the cross-sectional area of fluid path 243 thatreceives fluid from the patient. It is also contemplated that tubing 240may be configured to also define a second fluid path, either in themanner discussed above and illustrated in FIG. 24, or in the mannerillustrated in FIG. 30. The illustrated embodiment is not intended to belimiting in any way.

As illustrated in FIG. 56, patient interface 260 may include a head gearthat includes a strap 245 that is configured to be received by an ear ofthe patient and is also connected to the tubing 240 so as to supporttubing 240 and provide outward tension. As illustrated, strap 245includes an opening 248 for receiving the ear, and a holding portion 249that is configured to engage a portion of the tubing 240 and allow thetubing 240 to pass therethrough without creating a kink in the tubing.In the embodiment shown, holding portion 249 includes opening 246through which tubing 240 passes. The present invention contemplatesmanufacturing strap 245 from a material or combination of materials thatare suitable for processes such as injection molding. As such,identifying information, such as the product or company name, could beeasily added to the outer surface of loop portion 247. The illustratedembodiment is not intended to be limiting in any way.

While each of the embodiments are described above in terms of theirstructural arrangements, it should be appreciated that the presentinvention also covers the associated methods of using the embodimentsdescribed above.

Although the invention has been described in detail for the purpose ofillustration based on what is currently considered to be the mostpractical and preferred embodiments, it is to be understood that suchdetail is solely for that purpose and that the invention is not limitedto the disclosed embodiments, but, on the contrary, is intended to covermodifications and equivalent arrangements that are within the spirit andscope of the appended claims. For example, it is to be understood thatthe present invention contemplates that, to the extent possible, one ormore features of any embodiment can be combined with one or morefeatures of any other embodiment.

1. A patient interface comprising: a body portion configured tocommunicate with a first fluid path; a first nostril interface extendingfrom the body portion, wherein the nostril interface communicates withthe first fluid path; and a first securement portion extending from thebody portion proximate the nostril interface, wherein the securementportion is constructed and arranged to engage an exterior surface of apatient's nose to secure the patient interface to such a patient's nose.2. A patient interface according to claim 1, wherein the securementportion is biased toward the first nostril interface responsive to thesecurement portion being disposed on the patient's nose.
 3. A patientinterface according to claim 1, further comprising a first tubing thatdefines the first fluid path.
 4. A patient interface according to claim3, further comprising a strap coupled to the tubing and adapted tosupport the tubing, the strap being configured to be received by an earof a patient.
 5. A patient interface according to claim 1, wherein thebody portion is communicates with a second fluid path and furthercomprising a second nostril interface extending from the body portionand operatively coupled to the second fluid path.
 6. A patient interfaceaccording to claim 5, further comprising a first tubing that defines thefirst fluid path; and a second tubing that defines the second fluidpath.
 7. A patient interface according to claim 6, further comprising astrap for supporting the second tubing, the strap being configured to bereceived by an ear of the patient.
 8. A patient interface according toclaim 5, wherein the second nostril interface is configured and arrangedto remain below a patient nose responsive to the patient interface beingworn by such a patient, and includes at least one orifice definedtherein to delivery fluid to or receive fluid from such a patient.
 9. Apatient interface according to claim 1, further comprising aphysiological function sensor connected with the first securementportion for engagement with the skin of a nose of such a patient, andwherein the physiological function sensor generates a signal based on aphysiological function measurement.
 10. A patient interface according toclaim 9, wherein the sensor comprises an emitter for emitting a signaland a detector for detecting the signal.
 11. A patient interfaceaccording to claim 10, wherein the emitter comprises at least one lightsource and the detector comprises a photodetector.
 12. A patientinterface according to claim 1, further comprising a second securementportion constructed and arranged to engage an interior surface of apatient's nose such that a portion of a nose is disposed between thefirst securement portion and the second securement portion.
 13. Apatient interface according to claim 12, further comprising aphysiological function sensor connected with the first securementportion, the second securement portion or both for engagement with theskin of a nose of such a patient, and wherein the physiological functionsensor generates a signal based on a physiological function measurement.14. A patient interface according to claim 13, wherein physiologicalfunction sensor is disposed on the first securement portion, the secondsecurement portion or both such that (a) the emitter engages an externalsurface of a portion the nose and the detector engages an internalsurface of a portion of the nose, (b) the detector engages the externalsurface of a portion of the nose and the emitter engages the internalsurface of a portion of such nose, (c) the emitter and the detector bothengage the external surface of the nose, or (d) the emitter and thedetector both engage the internal surface of the nose.
 15. A patientinterface comprising: an appliance portion including a nostrilinterface, the nostril interface being configured to be received by apatient's nostril and to provide fluid communication between the nostriland a fluid path; and a physiological function sensor connected with theappliance portion for engagement with the skin of the nose of thepatient and generating a signal based upon a physiological functionmeasurement.
 16. A patient interface according to claim 15, wherein thesensor comprises an emitter for emitting a signal and a detector fordetecting the signal.
 17. A patient interface according to claim 15,wherein the appliance portion also includes: a body portion configuredto communicate with the fluid path; and a securement portion extendingfrom the body portion, wherein the securement portion is disposedproximate the nostril interface and constructed and arranged to engagean exterior surface of the patient's nose, and wherein the nostrilinterface and the securement portion cooperate to secure a portion ofthe patient's nose therebetween.
 18. A patient interface according toclaim 17, wherein at least a portion of the sensor is disposed on thesecurement portion such that the portion of the sensor engages theexterior surface of the portion of the patient's nose.
 19. A patientinterface according to claim 18, wherein (a) the emitter and thedetector are disposed on the securement portion and engage the exteriorsurface of the patient's nose, (b) the emitter is disposed on thesecurement portion and engages the exterior surface of the patient'snose and the detector is disposed within the nostril and engages aninterior surface of the portion of the patient's nose, (c) the detectoris disposed on the securement portion and engages the exterior surfaceof the patient's nose and the emitter is disposed within the nostril andengages an interior surface of the portion of the patient's nose, or (d)the emitter and the detector are disposed within the nostril and engagethe interior surface of the patient's nose.
 20. A patient interfaceaccording to claim 15, wherein the emitter and the detector are biasedtoward each other.